Ayman Siam was killed in a joint operation by Israel's internal security agency, Shin Bet, and Israeli Defence Force (IDF), channel 10 said.
He was reportedly killed in a strike when he was driving in a vehicle in the southern Gaza Strip.
Siam is said to be behind the barrage of rocket attacks that have pounded the southern areas of Israel uninterrupted over the last five days, the channel reported.
However, Hamas denied reports of Siam's death.
