Well Yincan 4 is the first parameter well for Sinopec in Yinchuan District, the purpose of drilling is to investigate the stratigraphic sequence of Yinchuan basin and the development of Qingshuiying formation hydrocarbon source rock. According to the complicated conditions in drilling process, such as cementing, loose and collapsing in upper formation, bit bouncing in gravel layer of Ganhegou formation, mud pollution by intrusive fluid in Qingshuiying formation, drilling into a large section of unexpected salt gypsum layer and lost circulation of drilling fluid in mudstone fracture of Qingshuiying formation, which were considered in the design of wellbore structure and optimization of hydraulic parameters, straight screw drilling tool and inclining prevention BHA were used with large discharge and light pressure in the large section construction to effectively prevent bit bounce, high drilling speed and good well quality were achieved. The drilling fluid system suitable for the salt gypsum layer in this area is explored and the best ROP record of 39.09m/h is created with φ444.5mm bit.