Can I use Perish Song on a sleeping Pokemon?

Question

I know this question is kind of stupid, but I just want to make sure my team works great.

Answer 1

You can use it on a sleeping Pokemon, but a sleeping Pokemon with Soundproof Ability will not work.

All Pokémon on the field when Perish Song is used become affected by it, except Pokémon with the Ability Soundproof; these Pokémon faint at the end of the 3rd turn after being affected. If an affected Pokémon switches out with Baton Pass, Perish Song will still affect the Pokémon switched in, even if it has the Ability Soundproof.
Since it does not do damage, Perish Song is unaffected by things such as the Focus Sash and Magic Guard.

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Source - Bulbapedia
Hope this helps!

Answer 2

Short answer, Yes.

Source: experience