The Water Evaluation and Planning (WEAP) model was invented by the Stockholm Environment Institute (SEI) to assist planning and management issues related with the development of water resources. The WEAP model can be applied to agricultural site and other sectors; and it can also tackle a large scope of problems encompassing water demand analyses, water saving, optimizing available water distribution and cost-profit analyses [1]. In this study, the WEAP model is introduced to look at the performance of the effect of different agricultural irrigation scenarios on special type of rice variety, i.e. MRQ76, planted in Wasan padi field, situated at Brunei-Muara District, Brunei Darussalam. Specifically, we apply the WEAP-MABIA model (based on soil-water balance approach) to perform evaluation of irrigation scheduling for three different rice growing seasons. We found that the WEAP model is a good model for providing the best irrigation scheduling strategy for optimum rice yield and efficient water management.