Sean Kingston is showing signs of improvement….

The R&B singer is awake and alert in his hospital bed….and is getting better everyday.

According to TMZ, Sean’s friends and family have been inundating his hospital room in Miami since the accident — and he is communicating through nods and sign language.

It’s a big improvement since the day of his jet ski crash on Sunday — when his injuries were so bad, he had to be treated in the trauma ward … before he was transferred to the ICU.

Last we checked, Kingston was still in critical condition — and doctors expect to keep him hospitalized for another couple of weeks.