The utility model relates to a connecting piece with a fine adjustment function. The connecting piece is characterized by comprising a screw, a bearing part, an expansion screw, a spring ring and a connecting rod, an opening is formed in the rear end of the screw; the front end and the rear end of the bearing part are in a step shape. the outer diameter of the front end of the bearing part is smaller than the outer diameter of the rear end of the bearing part and the inner diameter of the opening; the front end of the bearing part is elastic, an expansion opening is formed in the middle of thefront end of the bearing part, the expansion nail is matched with the expansion opening to enable the outer diameter of the front end of the bearing part to be increased, the spring ring is arrangedbetween the rear end of the bearing part and the opening, a mounting groove is formed in the rear end of the bearing part, and the connecting rod is arranged in the mounting groove. According to the utility model, the connection mode can be flexibly adjusted, and the vibration between equipment can be absorbed in the use process without directly bearing force on the connecting rod.