Since news of his passing his Harry Potter co-stars have paid tribute to the star.
J.K Rowling shared her sadness over the news, tweeting: "My thoughts are with Rima and the rest of Alan's family. We have all lost a great talent. They have lost part of their hearts."
Actress Emma Thompson, who starred with Rickman in Harry Potter, Sense and Sensibility and Love Actually, penned an emotional tribute.
"Alan was my friend and so this is hard to write because I have just kissed him goodbye.
"What I remember most in this moment of painful leave-taking is his humour, intelligence, wisdom, and kindness. His capacity to fell you with a look or lift you with a word.
"That intransigence which made him the great artist that he was - his inedible and cynical wit, the clarity with which he saw most things, including me, and the fact that he never spared me the view. I learned a lot from him.
"He was the finest of actors and directors. I couldn't wait to see what he was going to do with his face next. I consider myself hugely privileged to have worked with him so many times and to have been directed by him.
"He was the ultimate ally. In like, art and politics. I trusted him absolutely.
"He was, above all things, a rare and unique human being and we shall not see his like again."
Daniel Radcliffe, the star of Harry Potter shared his memories of the star on his Google+ account, writing: "Alan Rickman is undoubtedly one of the greatest actors I will ever work with."
He also said Rickman is also, one of the loyalest and most supportive people he's ever met in the film industry.
"He was so encouraging of me both on set and in the years post-Potter. I'm pretty sure he came and saw everything I ever did on stage both in London and New York. He didn't have to do that. I know other people who've been friends with him for much much longer than I have and they all say 'if you call Alan, it doesn't matter where in the world he is or how busy he is with what he's doing, he'll get back to you within a day'".
Radcliffe said Rickman was the opposite of Snape, that he was extremely kind, generous, self-deprecating and funny.
"As an actor he was one of the first of the adults on Potter to treat me like a peer rather than a child. Working with him at such a formative age was incredibly important and I will carry the lessons he taught me for the rest of my life and career. Film sets and theatre stages are all far poorer for the loss of this great actor and man," Radcliffe said.
He then shared a photo from the set of Harry Potter saying: "I like this photo."
"It was taken, if I'm not mistaken, while rehearsing a scene where Alan clipped me and Rupert round the back of a head with a book. We all, apparently, found this hard to do without laughing."
Radcliffe's co-star Emma Watson, who played Hermione Granger, also shared a message on social media.
The Weasley twins both tweeted their shock:
Shocked & sad to hear Alan Rickman has passed away. One of the nicest actors I've ever met.Thoughts and prayers with his family at this time