Rosenior, who played for Fulham in the Premier League between 2003 and 2007, said that he would put his love for the club to one side in order to help Hull take three important points.
"West Ham is a club close to my heart because my dad played for them and I was brought up around the club," Rosenior told PA.
"It was a fantastic place to be around and I used to watch all their games. I even used to have little West Ham bed sheets!
"I know all about them. But our job is to win games in the Premier League."
The game takes place at the KC Stadium on Saturday afternoon.