In many areas of Qaidam Basin，such as Yingxiongling，Ganchaigou and Xiandong，the shallow strata have poor lithology， loose cementation，fracture development，and frequently-occurred loss-return leakage in the process of drilling，which have seriously restricted the speed of drilling and affected the safety of drilling. This is a regional problem that needs to be solved urgently. Well Chaitan1 is a risk exploratory well located in Xiandong area. Conventional drilling fluid was used for the drilling of the surface section hole with a diameter of 660.4 mm. Leakage during the drilling was huge，and the plugging effect was not satisfactory. Therefore，it no longer possessed conditions to continue with the drilling. By using air-foam drilling technique and selecting the most suitable foaming agent and inhibitor for this well，the problem of frequently-occurred loss-return leakage in shallow strata has been solved，and the drilling cycle has been greatly shortened. By using the technique of sand cleaning-casing running，safe casing running has been realized in the well section with instable borehole and irregular hole diameters. The successful application of air-foam drilling technique in the Φ660.4 mm hole of Well Chaitan1 provides an approach and technical reserve for solving the problems of low pressure and likelihood for leakage and collapse in shallow strata during drilling in Qaidam Basin.