The invention discloses a solar hot air collector installed with horizontally inserted, densely arranged and jacking screwing hermetic evacuated solar collector tubes, which comprises an air duct, necking reduction screwing hermetic evacuated solar collector tubes, an air director, a fixed support and jacking tailstocks. The air duct is longitudinally installed and fixed at one end of the support, coaxial holes for inserting the screwing hermetic evacuated solar collector tubes are arranged at the same side of the inner tube of the air duct, or the air duct is longitudinally installed and fixed in the middle of the support, and coaxial holes for inserting the screwing hermetic evacuated solar collector tubes are arranged at the two sides of the inner tube of the air duct; the thread reducing tube joints of the screwing hermetic evacuated solar collector tubes are inserted and screwed tightly into the screw buckles of the pores of the inner tube of the air duct, the tail ends of the evacuated solar collector tubes are jacked tightly by the jacking tailstocks, the necking reduction screwing hermetic evacuated solar collector tubes are longitudinally sealed and installed on the poresof the inner tube of the air duct, and straight tube air directors which are positioned by supporting slips are installed in the tube cavities of the evacuated solar collector tubes. The invention improves the stability of a solar water heater system, realizes the perfect combination with buildings, and adds functions of heat insulation and building materials to the solar hot air collector under the premise of maintaining the heat collecting function thereof.