The 23-year-old Czech international was in London on Tuesday to undergo a physical examination and Fulham are happy that he can handle the rigours of Premier League life.
"He's signed and I am happy with him," said boss Martin Jol. "He is a very talented player.
"He's a good midfield player and played against England [in the Under-21 European Championships] and got two assists so he is full of confidence.
"He knows he can play against English teams and that helps. He signed the contract yesterday.
"He had a very good tournament and was very decisive in games.
"That gave us confidence and he has been on our radar for at least a year.
"The Fulham scouts knew him and had very good reports on him."
The deal is reportedly worth £700,000 and Jol believes Gecov is a good addition to the Cottagers' squad.
"He is a typical midfield player and he is relatively young," he added.
"He is aggressive and, as I've said, I am happy he is on board."
Gecov is delighted to have secured a switch to Craven Cottage and admits he cannot wait to get started.
He told isport.blesk.cz: "I am enormously happy because it has always been my dream to play in the Premier League."
Gecov's agent claims his client should have no problem adjusting to life in England, with Fulham having put him through a thorough medical.
Jiri Muller said: "It was very demanding. I have never seen such a thorough medical as this. About 20 doctors and other experts checked Marcel.
"He underwent physical, functional, medical and psychological tests and everything turned out okay in the end."