|Relations||Gwen Tennyson (daughter), Lili Tennyson (wife), Max Tennyson (father), Carl Tennyson (brother), Ben Tennyson (nephew), Verdona Tennyson (mother)|
|Base of Operations||Gwen's House|
|Group Affiliation(s)||Tennyson Family|
|Species||1/2 Human, 1/2 Anodite|
|Gallery | Quotes | Appearances | Merchandise|
Gwen Tennyson and Ken Tennyson's father, the son of Max Tennyson, and husband of Lili Tennyson, he was first mentioned in the Ben 10 episode, "Goodbye and Good Riddance" having gotten a new job and they were being relocated to Bellwood. Frank knows of his father's history as a Plumber and blamed it for why they are not close. Frank does not approve of Gwen's relationship with Kevin Levin
- Verdona Tennyson states that Frank always knew when she was eavesdropping on him.