In order to reveal effects of seasonal freeze-thaw cycles and soil properties on soil erodibility in the black soil region of Northeast China, the effects of freeze-thaw cycles and soil properties on soil shear strength were analyzed through indoor freeze-thaw cycle simulation and direct shear tests in laboratory. Two different tested soils were collected from top soil (0-20 cm plough layer) at typical thin-layer black soil region (BX) in Binxian County and typical thick-layer black soil region (KS) in Keshan County of Heilongjiang Province. The results showed that:(1) Freeze-thaw alternations reduced soil shear strength, cohesion and internal friction angle for both tested soils (BX and KS). After one time of freeze-thaw cycle, soil shear strength of BX and KS tested soils decreased by 3.9% and 9.2%, the soil cohesion decreased by 15.2% and 29.4%, and internal friction angle decreased by 1.4% and 3.6%, respectively. After seven times of freeze-thaw cycle, soil shear strength of the two tested soils decreased by 9.1% and 15.1%, soil cohesion decreased by 40.7% and 74.5%, and soil bulk density decreased by 6.7% and 9.2%, respectively. Due to the differences in the contents of soil organic matter, soil water stable aggregate and clay content, the decreasing extent of shear strength, cohesion and internal friction angle of KS tested soil were all greater than those of BX tested soil. (2) Soil shear strength decreased gradually and then tended to be stable with the increasing of freeze-thaw cycles for both tested soils. Moreover, the first freeze-thaw cycle had the greatest damage to soil shear strength, the decrement of soil shear strength after the first freeze-thaw cycle for both BX and KS soils occupied 43.4% and 61.0% of the total decrement of soil shear strength after seven freeze-thaw cycles, respectively; the decrement of soil cohesion after the first freeze-thaw cycle accounted for 37.3% and 39.4% of the total decrement of soil cohesion after seven freeze-thaw cycles, respectively. (3) Soil shear strength had significant positive correction with soil bulk density and mean weight diameter of soil aggregates (MWD), while it had significant negative correction with freeze-thaw cycles.