Mr Shen came to Phuket for his honeymoon with his new wife, Wen Wen, 26, and eight friends.
This morning, around 11 am, the group rented jet-skis. Soon after, the machine Mr Shen was riding was in collision with the parasailing speedboat, just off Loma Park.
The owner of the jet-ski, Sunan Thongren, seeing the smash, rushed into the sea with his staff and pulled the unconscious Mr Shen from the water.
Mr Shen was taken to Patong Hospital and then, because of the severity of his condition, was transferred to Phuket International Hospital where he remains in a coma.
Pol Lt Thawatchai Srimai of Kathu Police said officials are expected to call a meeting soon to discuss who will pay damages to whom.