The invention belongs to the technical field of assembly machinery and particularly relates to an assembly detection machine for blood taking needles. The machine comprises rack, a work table, a blood taking needle loader and an outer cover loader. The work table is arranged on the rack. A running passage, a delivery unit, a needle pressing unit, a detection unit, an outer cover assembly unit and a screening unit are arranged on the work table. A needle pressing support, a needle pressing sliding block and a needle pressing drive unit are arranged on the work table. The needle pressing sliding block is arranged on the needle pressing support, and a needle pressing driving unit drives the needle pressing sliding block to move vertically. The needle pressing unit and the detection unit are both arranged on the needle pressing sliding block. By means of the machine, needle pressing and detection are completed automatically through the needle pressing unit and the detection unit, the operation consistency is good, defectives cannot be produced easily, and the yield is high; besides, the blood taking needles are detected through the detection unit, so that rejects can be found timely, and by the matching of the screening unit, defectives can be eliminated; the whole moving process of the blood taking needles is completed with the delivery unit, participation of people is not needed, and the production efficiency is high.