Abstract: As a fundamental natural and strategic resource, water resources have gradually become a controlling factor limiting the sustained and stable development of regional economy and society. In order to implement water resources as the maximum rigid constraint requirement and realize the rational development and utilization of water resources maximization in the drought-stricken areas of western Guangdong, taking Guangdong water resources allocation project around the Beibu Gulf as an example, based on an analysis of the water consumption change trend from 2012 to 2020 in the project demand area, the multi-level index method, entropy value method and weighted average method are used to construct a rigid constraint evaluation system for water conservation, which is used to study the total water consumption and the rigid constraint degree of each water conservation index at the water supply end and the user end in 2020 and in 2035.The results show that the total water consumption and the water consumption of all industries in the demand area of Guangdong water resources allocation project around the Beibu Gulf in the past decade have shown a slow downward trend, and the water consumption structure has gradually become reasonable. However, the current water conservation level in 2020 is poor. Except for the total water consumption index, the other indicators of the constraint layer do not meet the requirements of rigid water conservation constraints. The design has a strong degree of water conservation rigid constraint in 2035, and the water conservation indicators in the constraint layer meet the evaluation criteria. The comprehensive score of the water conservation indicators in the expected layer is 90.7, and the water conservation rigid constraint level is high. The project design meets the national and Guangdong water conservation rigidity constraint requirements and the primary premise of “saving water first and then transferring water” in water transfer project. However, it should further strengthen the work related to household water conservation, agricultural water conservation irrigation and efficient water conservation irrigation. The research findings can provide a reference for the analysis of water transfer areas and objects, and optimization of engineering design schemes for the Guangdong water resources allocation project around the Beibu Gulf. The established water conservation rigid constraint evaluation system has a reference significance for similar water transfer projects.