Sylvester J. Pussycat Jr., simply known as Sylvester Jr., is an animated cartoon character in the Warner Bros. Looney Tunes and Merrie Melodies series.

He was created by Robert McKimson.

Sylvester Jr. appeared in the following shorts: After the original Looney Tunes shorts, Junior would show up sporadically in later years.

He is seen in one of the "Mysterious Phenomenon of the Unexplained" shorts of the Stranger Than Fiction Looney Tunes web shorts compilation DVD alongside his father on a camping trip interrupted by Bigfoot.

He appears as a boss in the third world in the video game The Bugs Bunny Birthday Blowout, riding his skateboard.