The 44-year-old stepped down from his post at Camp Nou in order to continue further cancer treatment, prompting messages of support from across the world on social media.
Barca president Sandro Rosell confirmed the news at a press conference on Friday evening, revealing that Vilanova was due to undergo further treatment to his throat cancer which would make it "impossible for him to continue as coach."
Former Barca stars Eric Abidal and David Villa also sent their best wishes via personal Twitter accounts, and Vilanova's son retweeted the message: "Tito is not retiring. He will just concentrate on the most important game of his life."
Below is a selection of some of the many messages of support from all corners of the footballing globe.
Strength, Tito. You're great. Always by your side. Big, big hug.
A big hug for Tito and all his family. I wish you lots of strength to keep fighting in this very difficult moment.
Everyone at Chelsea Football Club sends their best wishes to Tito Vilanova for a speedy recovery.
Jose Mourinho, his coaching staff and the Chelsea players also all send their best wishes to Tito Vilanova for his fast recovery.
We would like to send our support, affection, and solidarity to Tito Vilanova, his family, friends, and FC Barcelona. #GetWellSoonTito
Very sad that FC Barcelona coach Tito Vilanova has resigned due to his medical condition. Wish him all the very best.
Strength, Tito! We are with you!
All the support in the world for Tito and his family. We are all with you! #ànimsTito
All my support for Tito and his family, we are with you #getwellsoonTito #AnimsTito
Lionel Messi (via Facebook):
Strength, Tito! We are all with you in this fight
All the strength and luck to #TitoVilanova. I wish you a quick recuperation.
Football is fleeting with its triumphs and troubles. All my strength to Tito Vilanova and his family. Animo!! You're going to win this game!
Todo mi apoyo para Tito Vilanova, amigos y familia! Animo y mucha fuerza! // All my support to Tito Vilanova, friends and his family!