This answer is incorrect. It was written with the assumption that the OP was quoting the rules text from an official source which, it seems, they were not.

The official text for the ability is "another creature you can see" not "a creature you can see." In fact, even the lead rules designer Jeremy Crawford made the mistake of assuming the "a creature" wording was correct in his tweet below.

It's comforting to know that even Jeremy can make this mistake but the fact remains that ANOTHER creature must be the target of the Barbarian's ability. See my second answer instead.

I can't delete this answer because it has been accepted so, I'm editing it to put this disclaimer in until it can be deleted and leaving the original answer below for archival purposes. My deepest apologies for the damage I have cause by answering incorrectly.

Yes, the Barbarian can benefit from his/her own Spirit Shield

Even though Spirit Shield is an ability not a spell, the rules on spellcasting talk about a parallel situation with (spell) effects:

Targeting Yourself

If a spell targets a creature of your choice, you can choose yourself, unless the creature must be hostile or specifically a creature other than you. If you are in the area of effect of a spell you cast, you can target yourself.

Assuming the Barbarian can see himself, he can target himself to benefit from Spirit Shield. Of course, the flipside of this is that Spirit Shield would not be available for use on an ally until the next turn, so doing this does have an opportunity cost.

There may be circumstances where the Barbarian cannot see himself: if he is blinded or in the dark for example. But otherwise, your interpretation is correct (and has been affirmed by Jeremy Crawford in an unofficial tweet).

This answer is incorrect.

It was written with the assumption that the OP was quoting the rules text from an official source which, it seems, they were not.

The official text for the ability is "another creature you can see" not "a creature you can see." In fact, even the lead rules designer Jeremy Crawford made the mistake of assuming the "a creature" wording was correct in his tweet below.

It's comforting to know that even Jeremy can make this mistake but the fact remains that ANOTHER creature must be the target of the Barbarian's ability. See my second answer instead.

I can't delete this answer because it has been accepted so, I'm editing it to put this disclaimer in until it can be deleted and leaving the original answer below for archival purposes. My deepest apologies for the damage I have cause by answering incorrectly.

Yes, the Barbarian can benefit from his/her own Spirit Shield

Even though Spirit Shield is an ability not a spell, the rules on spellcasting talk about a parallel situation with (spell) effects:

Targeting Yourself

If a spell targets a creature of your choice, you can choose yourself, unless the creature must be hostile or specifically a creature other than you. If you are in the area of effect of a spell you cast, you can target yourself.

Assuming the Barbarian can see himself, he can target himself to benefit from Spirit Shield. Of course, the flipside of this is that Spirit Shield would not be available for use on an ally until the next turn, so doing this does have an opportunity cost.

There may be circumstances where the Barbarian cannot see himself: if he is blinded or in the dark for example. But otherwise, your interpretation is correct (and has been affirmed by Jeremy Crawford in an unofficial tweet).

Yes, the Barbarian can benefit from his/her own Spirit Shield

Even though Spirit Shield is an ability not a spell, the rules on spellcasting talk about a parallel situation with (spell) effects:

Targeting Yourself

If a spell targets a creature of your choice, you can choose yourself, unless the creature must be hostile or specifically a creature other than you. If you are in the area of effect of a spell you cast, you can target yourself.

Assuming the Barbarian can see himself, he can target himself to benefit from Spirit Shield. Of course, the flipside of this is that Spirit Shield would not be available for use on an ally until the next turn, so doing this does have an opportunity cost.

There may be circumstances where the Barbarian cannot see himself: if he is blinded or in the dark for example. But otherwise, your interpretation is correct (and has been affirmed by Jeremy Crawford in an unofficial tweet).

This answer is incorrect. It was written with the assumption that the OP was quoting the rules text from an official source which, it seems, they were not.

The official text for the ability is "another creature you can see" not "a creature you can see." In fact, even the lead rules designer Jeremy Crawford made the mistake of assuming the "a creature" wording was correct in his tweet below.

It's comforting to know that even Jeremy can make this mistake but the fact remains that ANOTHER creature must be the target of the Barbarian's ability. See my second answer instead.

I can't delete this answer because it has been accepted so, I'm editing it to put this disclaimer in until it can be deleted and leaving the original answer below for archival purposes. My deepest apologies for the damage I have cause by answering incorrectly.

Yes, the Barbarian can benefit from his/her own Spirit Shield

Even though Spirit Shield is an ability not a spell, the rules on spellcasting talk about a parallel situation with (spell) effects:

Targeting Yourself

If a spell targets a creature of your choice, you can choose yourself, unless the creature must be hostile or specifically a creature other than you. If you are in the area of effect of a spell you cast, you can target yourself.

Assuming the Barbarian can see himself, he can target himself to benefit from Spirit Shield. Of course, the flipside of this is that Spirit Shield would not be available for use on an ally until the next turn, so doing this does have an opportunity cost.

There may be circumstances where the Barbarian cannot see himself: if he is blinded or in the dark for example. But otherwise, your interpretation is correct (and has been affirmed by Jeremy Crawford in an unofficial tweet).

##Yes, the Barbarian can benefit from his/her own Spirit Shield##

Even though Spirit Shield is an ability not a spell, the rules on spellcasting talk about a parallel situation with (spell) effects:

Targeting Yourself

 

If a spell targets a creature of your choice, you can choose yourself, unless the creature must be hostile or specifically a creature other than you. If you are in the area of effect of a spell you cast, you can target yourself.

Assuming the Barbarian can see himself, he can target himself to benefit from Spirit Shield. Of course, the flipside of this is that Spirit Shield would not be available for use on an ally until the next turn, so doing this does have an opportunity cost.

There may be circumstances where the Barbarian cannot see himself: if he is blinded or in the dark for example. But otherwise, your interpretation is correct (and has been affirmed by Jeremy Crawford in an unofficial tweet).

Yes, the Barbarian can benefit from his/her own Spirit Shield

Even though Spirit Shield is an ability not a spell, the rules on spellcasting talk about a parallel situation with (spell) effects:

Targeting Yourself

If a spell targets a creature of your choice, you can choose yourself, unless the creature must be hostile or specifically a creature other than you. If you are in the area of effect of a spell you cast, you can target yourself.

Assuming the Barbarian can see himself, he can target himself to benefit from Spirit Shield. Of course, the flipside of this is that Spirit Shield would not be available for use on an ally until the next turn, so doing this does have an opportunity cost.

There may be circumstances where the Barbarian cannot see himself: if he is blinded or in the dark for example. But otherwise, your interpretation is correct (and has been affirmed by Jeremy Crawford in an unofficial tweet).