Abstract: Based on detailed geological work, the authors investigated three geological sections in Hexi and Dasanjie area within the northern part of Lanping Basin. At least two sets of Upper Triassic gypsum-bearing horizons were identified. The upper horizon is in the upper member of Sanhedong Formation(T3s2) and its salt-bearing materials are quite simple in content, composed mainly of celestine and gypsum with a very small amount of barite. The lower horizon is within the lower member of Sanhedong Formation (T3s1), with the saline material being also made up of celestine. The gypsum-bearing horizons are of the same attitude as the overlying and overlying carbonate layers. The rock associations of the horizons are different in different places, so that the stratigraphic sequences can't be laterally correlated with each other. The salt-bearing horizons present some syn-sedimentation characteristics, but are different from the evaporate deposits formed by evaporation.