Positioning device for steel structural member assembly

The invention discloses a positioning device for steel structural member assembly in the technical field of steel members, and the positioning device comprises a movable supporting assembly, the top of the movable supporting assembly is connected with a vertical height adjusting assembly, and the top of the vertical height adjusting assembly is connected with a roof panel end clamping assembly through a positioning block; the roof panel end clamping assembly comprises a limiting groove and an adjusting air cylinder set connected in the limiting groove through a wedge-shaped base, the top of the adjusting air cylinder set is connected with a retaining rod through an air cylinder telescopic rod, the two ends of the retaining rod penetrate through a limiting frame, and the lower end of the limiting frame is in bearing connection with the limiting groove through a round rod. The alignment assembly is installed at one end of the clamping plate and used for aligning the welding positions of the roof panel and the r