The effects of different biochar additions on water transport in red soils were investigated by an indoor soil column simulation test. Five groups with biochar dosage rates of 1% (T1), 2% (T2), 3% (T3), 4% (T4), and 5% (T5) were set, along with a control group without biochar (CK). The analysis focused on the effects of these treatments on wet front (Zf), cumulative infiltration (I), and soil moisture content, and the performance of different infiltration models was evaluated by fitting the infiltration process. According to the test results, wet front migration initially decreased, then stabilized, and subsequently declined as the biochar content increased; the maximum wet front migration was observed in T1 at 44.2 cm, while the minimum was seen in T5 at 18.1 cm. Compared to the CK group, wet front migration decreased by 23.3% and 26.3% in T3 and T4, respectively. Cumulative infiltration also exhibited the same variation trend as the wet front migration, with maximum infiltration in CK at 84.3 cm and minimum in T5 at 26.0 cm; while that for T3 and T4 were measured at 30.4 cm and 30.1 cm, respectively. Soil water content was higher in treatment groups compared to the CK group, indicating that biochar can improve soil water retention performance. It was found that the Kostiakov model had the best fitting effect when comparing the RRMSE and R2 results of different models. These results can provide valuable insights for effective water management practices in hilly red soil regions.