Jack Grassel is an American jazz guitarist, teacher, and author from Milwaukee, Wisconsin.

He worked with Rosemary Clooney, Slide Hampton, Stanley Jordan, Ed Thigpen, and Nancy Wilson.

As a result of the first two records of his compositions "Magic Cereal" and "If You're Too Crazy", he was featured in the New Talent section of Guitar Player magazine and became a contributing writer.

His friend, guitarist Kirk Tatnall, built one, too, and they recorded the album Live at the Uptowner with their hybrid instruments.

He married vocalist Jill Jensen, and they recorded five albums: Seems Like Dreams, It's About the Music, Snow People.