The on-loan Chelsea striker injured his left knee when clashing with Tottenham goalkeeper Hugo Lloris during Sunday's goalless draw at Goodison Park.
Lloris controversially remained on the pitch despite being knocked unconscious but Lukaku had to be substituted and was unable to put any weight on his knee as he departed the action.
However, the 20-year-old Belgium international has since made a good recovery - he posted a picture online of a bag of frozen vegetables that he was using to reduce the swelling - and is now back in training.
Martinez told the club's official website: "We're very pleased with Romelu's recovery.
"We were a little worried on Monday but he reacted well to training and is fully fit to train, which is really good news.
"Everyone else has been fine - we didn't collect any other knocks or bruises on Sunday."
Martinez will be keen to have Lukaku in his squad at Selhurst Park as he has already lost the services of Arouna Kone who faces a long spell out with a cartilage problem.
The 29-year-old was injured after coming on as a substitute in the 2-1 home win over Hull on Saturday October 19.