Strain-controlled triaxial unconsolidated and undrained shear tests were used to study the strength of compacted loess from the Qinghai region.The tests were conducted at moisture contents of 14% and 17% at 97% compaction，and 95% and 96% compaction at moisture content of 17%. The specimen diameter was 3.91 cm，and the height was 8 cm.To analyze the stress-strain behavior，the Duncan-Chang model was used.The test results suggest that the deviator stress increases as the axial strain increases at different confining pressures regardless of initial moisture and compaction.The relationship between deviator stress and axial strain is close to hyperbolic.The deviator stress and the initial tangent modulus increase as the confining pressure increases.At constant confining pressure，the deviator stress at failure decreases with increasing moisture and increases with increasing compaction.With increasing moisture content，the cohesion，friction angle，K，and Rf decrease，whereas porosity n increases.With increasing compaction，the cohesion，friction angle，K，and Rf increase，whereas n decreases.