Purpose <p>As a typical and widely practiced soil and water conservation measure, straw incorporation has significant effects on reducing runoff and soil loss from sloping cropland. In the northeastern black soil region of China, freeze-thaw action during early spring may cause severe soil erosion. However, the impact of this on the benefits of straw incorporation is unknown.</p> Materials and methods <p>Therefore, this study investigated the soil erosion process and morphological characteristics of rill on slopes under different flow rates (2 and 4&#xa0;L min^− 1), thawed depths (thawed of 3, 6, and 9&#xa0;cm, unfrozen treatments), and straw incorporation rates (0%, 30% and 80%) through scouring experiments.</p> Results and discussion <p>The results showed a significant increase in the runoff initiation time (maximum increase of 87.15%) with increasing straw incorporation rates in all treatments. The peak sediment yields of the unfrozen (without freeze-thaw treatment) and thawed treatments (i.e., 3, 6, and 9&#xa0;cm thawed depths) under 2&#xa0;L min^− 1 without straw incorporation conditions were 342.85, 582.96, 308.41, and 440.17&#xa0;g m^− 2 min^− 1, respectively. Increasing to 4&#xa0;L min^− 1, sediment yield increased by 1.44–3.19 times. Compared to 0% straw incorporation rates, treatments with 30% and 80% straw incorporation rates reduced peak sediment yield by about 4 and 10 times, respectively. In addition, as the depth of thawing increased, the depth of rills gradually increased while the width became smaller. When straw incorporation rate was increased, the depth of rills decreased significantly.</p> Conclusion <p>These findings carry significant implications for climate-adaptive soil management. The amplified erosion risks during spring thawed periods, especially with increased rainfall intensity, necessitate targeted straw incorporation strategies.</p>