How does Scooby Doo say uh oh?

Scooby Doo doesn't actually say "uh oh" in the traditional sense. He says "Ruh-roh". It's a catchphrase unique to him, and it's meant to sound like a mix of "uh oh" and "ruh-roh".

It's a classic cartoon sound effect that's become synonymous with the character himself. 😄