A solar collector of screw seal evacuated solar collector tubes longitudinally inserted, closely arranged and tightly pressed comprises a water tank, screw seal evacuated solar collector tubes, a fixed support and a tail stock for the evacuated solar collector tubes. A water inlet and a water outlet are arranged on the bladder of the water tank. The water tank is horizontally arranged at the upper end of the fixed support. The thread reducing tube heads of the screw seal evacuated solar collector tubes are inserted and tightly screwed in the screws of the tube holes of the bladder, and are sealed by seal rings and the tube holes of the bladder of the water tank. The screw seal evacuated solar collector tubes are longitudinally sealed and arranged in the tube holes of the bladder by the tightly pressing tail stock in the tail stock box of the bearing fixed support, and the screw seal evacuated solar collector tubes are longitudinally and closely arranged. Windshield rings sheathed on the tube walls of the screw seal evacuated solar collector tubes are arranged at the plug-in mounting parts of the screw seal evacuated solar collector tubes and an outer bucket. The present invention improves the stability and the durability of solar water heater systems, perfectly combines with building, and makes solar water heaters have thermal insulation and building material functions under the condition of having heat collection functions.