Kuyt celebrated his 100th Premier League appearance with two second-half goals as the title-chasing Reds saw off battling 10-man Hull 3-1 at the KC Stadium.
Benitez said: "Everybody is very pleased for him.
"Kuyt is a fantastic professional and is always working hard to score.
"He was very positive and we are really pleased for him."
Liverpool's performance lacked the intensity of that in Tuesday's pulsating 4-4 draw with Arsenal but Benitez did not feel his side were feeling the after-effects of that classic.
He added: "We were working very hard and we have to be satisfied.
"We were nervous because the pitch was terrible. The pitch was dry and the grass was long - it was difficult to pass the ball.
"You can make mistakes but it is part of the game and we have to accept the situation.
"The second half was better."