Seizō Katō (加藤 精三, Katō Seizō, February 14, 1927 – January 17, 2014) was a Japanese voice actor who worked for Haikyo (Tokyo Actor's Consumer's Cooperative Society).

Kato was born in Tokyo. He was noted for his role as Megatron and Galvatron from the 1st Transformers series until Transformers: The Headmasters. He also did the ADR for Takeshi Katō's character in Akira Kurosawa's Ran after the original actor had become injured.

He died of bladder cancer at a hospital in Itabashi, Tokyo.