The objective of this study was to reveal the soil and water conservation effects of different straw returning patterns at croplands in the black soil region of China. Based on simulated rainfall experiments at field croplands in situ, effects of three representative straw returning patterns (deep application of straw, smashed straw turnover, and no-tillage with straw mulching) on the processes of runoff rates and soil loss rates, total runoff and soil erosion amount, runoff and sediment reduction benefits at 50 and 100 mm/h rainfall intensities were analyzed. The traditional up- and down slope tillage was used as the control treatment. The results showed that: (1) The runoff rates for treatments of different straw returning patterns increased as the rainfall amount increased. Both the runoff rates and soil loss rates decreased in the order of up- and down slope tillage (CK) > deep application of straw > smashed straw turnover > no-tillage with straw mulching. (2) The straw returning treatments delayed the runoff yield time for 14.0 min at 50 mm/h and 4.8 min at 100 mm/h compared with the traditional up-and down slope tillage treatment, which could reflect the soil and water conservation effects of these straw returning measures. (3) The mean runoff reduction benefits for deep application of straw, smashed straw turnover, and no-tillage with straw mulching treatments were 36.8%, 53.9%, and 65.8%, and their mean sediment reduction benefits were 84.9%, 90.3%, and 96.8%, respectively. Therefore, the pattern of no-tillage with straw mulching had the best soil and water conservation effect in this study, which was followed in descending order by the patterns of smashed straw turnover and deep application of straw.