Faba bean (Vicia faba L.) is an important pulse crop known for its nitrogen-fixing characteristics and as a disease-break crop in crop rotations. Sowing time, scheduling of supplemental irrigation, and sowing rate are some of the agronomic managements which affect faba bean growth and yield. Calibrated models can be used to evaluate the impact of these on faba bean yield. In this study, the FAO AquaCrop model was calibrated and validated using two year experimental data on different watering regimes, sowing dates, and sowing rates in a semiarid environment of south-eastern Australia. AquaCrop adequately simulated the green canopy cover (CC), biomass development, grain yield, and soil water dynamics under different agronomic management conditions. AquaCrop simulated faba bean yield with 5.4% deviation, root mean square error (RMSE) of 0.53 t ha-1, normalised root mean square error (NRMSE) of 13.5%, index of agreement (d) of 0.95, and R2 of 0.84. The CC was simulated with RMSE of 14.3%, R2 of 0.81, and d of 0.88. The above-ground dry matter was predicted with RMSE of 2.7 t ha-1, R2 of 0.95, and d of 0.92. Except for end-of-season values, the soil water content was also correctly simulated at RMSE of 21 mm, R2 of 0.89, and d of 0.85. The growth and yield response of faba bean to supplemental irrigation, sowing time, and sowing rate was adequately simulated by the calibrated model. AquaCrp is a valuable decision support tool for predicting faba bean growth, yield, and soil water dynamics under a wide range of agronomic managements.