Abstract: Based on moulage analysis of bore-hole formed by hydro-fracturing,a method of account and error reliability analysis on longitudinal and transverse fracture rock-mass is proposed with Taylor expressions and iterative least-squares fitting.First,the bore-hole,fracture plane and earth coordinate system are confirmed,and cranny azimuth is confirmed by moulage curve.Then,stress component are calculated with Taylor expressions and iterative least-squaress fitting.Lastly,principle stress and its error are done.According to calculative method and geodesic datum,the maximal horizontal stress(13 MPa,113°or so) at Boreoll ZK6, Xuefeng Moutain,is educed.The result is similar to that of geologic reconnaissance and illuminates that the method is logical and applicable.