Provided is a floating core-pulling mechanism for pipe fitting forming. The floating core-pulling mechanism for pipe fitting forming can be used for replacing a traditional long-stroke hydraulic core-pulling structure. According to the floating core-pulling mechanism for pipe fitting forming, a guide groove is formed in a guide support, the guide groove and a floating core-pulling portion are in sliding fit through a guide pin, a reset spring is assembled between a base body and the floating core-pulling portion, a sliding wedge supports the guide support, a wedge base is provided with a slope, the sliding wedge and the slope are in sliding fit, a limiting link stopper is arranged corresponding to the sliding wedge, a pinch roller is connected with the lower end of a connecting rod, the upper end of the connecting rod is connected with an upper die, namely a movable die, of a die, when the connecting rod moves downwards, the sliding wedge and the limiting link stopper can be separated through the pinch roller, the connecting rod can enter the position between the sliding wedge and the limiting link stopper to push the sliding wedge, the limiting link stopper and the wedge base are arranged on a lower die, namely a stationary die, of the die, and the nature state of a telescopic device is the state that the size of a gap between the sliding wedge and the limiting link stopper is kept to be smaller than the outer diameter of the pinch roller.