Leslie Valdes is a Cuban-American writer and actor who voiced Señor Tucán, as well as several minor characters on Dora the Explorer and its spin-offs Go, Diego, Go! and Dora and Friends: Into the City!. He also wrote several episodes and served as staff writer during season 4.

He is the husband of the show's co-creator Valerie Walsh Valdes.
Roles
- Señor Tucán
- King Crab
- Moon
- Echo Bush
- Señor Burro
- Autobús
- Circus crowd (along with Jed Becker, Kailani Coba, Denise Dorn, Chris Gifford, and Alix Landry)
- Ringmaster
- Señor Shush
- Forest Creatures (from The Magic Stick, along with Jordan Smith-Howie and Omar Pastran)
- Townspeople (from Rojo, the Fire Truck and Dora, La Música)
- 10 Wheeler
- El Bote
- Robot Gate
- Roberto's Grandpa
- Isa's Rocket Ship (from Journey to the Purple Planet)
- Knights
- Lion Statue at Kinkajou's Castle
- Big Red Drum
- Fire chief on the Fire House intercom (from Job Day)
- Bear (from Baseball Boots)
- Giant-Giant (Seasons 4-5)
- Chucho
- Skinny Dwarf (one of the Seven Dwarves)
- Rabbit
- Helicoptero (from The Great Polar Bear Rescue)
- Saturn
- Trees (from Boots' Banana Wish)
- Walls (from Dora's Royal Rescue)
- Arco Iris (Go, Diego, Go)
- Dapple
- Dragon King
- Señor Tren
- Gus the Bus
- Big Bad Wolf (Dora Saves Fairytale Land)
Episodes written
Season 1
Season 2
Season 4
Season 7
Trivia
- In addition to his work on Dora the Explorer, Valdes is the co-creator of Nick Jr.'s recent series Santiago of the Seas (along with Valerie Walsh Valdes and Niki Lopez). He was also an executive producer/head writer during its first season.
- However, both he and Valerie left the show after the first season, most likely to work on the upcoming Dora reboot for Paramount+.
- Valdes served as head writer/producer on Disney's Mickey Mouse Clubhouse. His other writing credits include The Backyardigans and Handy Manny.
- He was one of the creators who wrote the least amount of episodes.
- He never wrote any episodes from Go, Diego, Go! or Dora and Friends: Into the City!.