Screw drilling technology was introduced to ZK1 geothermal well drilling construction in Zunyi of Guizhou, in order to meet the requirements of screw drilling technology on drilling fluid property and deal with the complicated geological conditions, a comprehensive analysis was made on the formation characteristics and complex degree as well as performance parameters of drilling fluid for drilling process. Drilling fluid proportioning experiment was carried out in laboratory. Through the application in this well, it showed that the drilling fluid has good properties of strong adaptability, moderate viscosity and reasonable filter loss with thin and compact mud cake, which can prevent borehole collapse and diameter shrinkage to reduce accident rate and can provide sufficient power for screw drilling to meet the requirements of screw drilling technology and improve drilling efficiency.