West died after a brief battle with leukemia at the age of 88. He was best known for playing the title character in the 1960s Batman series. Ward played his sidekick Robin.
"I am devastated at the loss of one my very dearest friends," Ward said in a statement to Variety. "Adam and I had a special friendship for more than 50 years. We shared some of the most fun times of our lives together. Our families have deep love and respect for each other. This is a terribly unexpected loss of my lifelong friend. I will forever miss him. There are several fine actors who have portrayed Batman in films. In my eyes, there was only one real Batman that is and always will be Adam West. He was truly the Bright Night."
Seth MacFarlane, who worked with West on the animated series Family Guy, remembered the late actor as a "friend" and a "joy to work with."
"Rest in Peace Adam West. We met once in 1987 and I was too embarrassed and too foolishly "cool" to tell you what you meant to my childhood," sci-fi and fantasy author Neil Gaiman said in a Twitter post.
"Ah dear Adam West. He was always so kind when we met. A real gent," offered Val Kilmer, who played Batman in Batman Forever.
"Adam West my after school hours were filled with excitement watching you battle fantastic Villains. You were a delight to meet on the convention circuit," Torchwood and Arrow star John Barrowman tweeted.