This study investigates how rural water resource accessibility influences water conservation practices and their impact on livelihoods in the Mvomero district, Tanzania. It explores the determinants of water conservation practices and their effects on food security and household income. The study used a cross-sectional design, collecting data from 490 households between October 2022 and December 2022. Structural equation modeling, multivariate probit, simple probit, and robust ordinary least square models were used for analysis. Results showed that agricultural productivity and sustainable water supply significantly influence water conservation. Water accessibility significantly influences participation in water conservation and environmental sustainability, while government regulations influence water accessibility. Determinants of water conservation practices include water quality, education, occupation, water proximity, and residence location. Probit and robust ordinary least square models showed that earth dams significantly increase food security and income, while water banks and guttering significantly influence food security and income. Water tanks were the most preferred water conservation practice, followed by rooftop catchment systems. The study recommends that policymakers prioritize investing in water infrastructure and encourage households to participate in water resource conservation to ensure sustainability and benefit societal development. The study highlights the urgent need for comprehensive and inclusive water management strategies to address water scarcity, especially in rural areas. It emphasizes the importance of understanding rural residents' behaviors regarding water accessibility and conservation to inform targeted policies and initiatives for sustainable water management and rural livelihoods.This study investigates how rural water resource accessibility influences water conservation practices and their impact on livelihoods in the Mvomero district, Tanzania. It explores the determinants of water conservation practices and their effects on food security and household income. The study used a cross-sectional design, collecting data from 490 households between October 2022 and December 2022. Structural equation modeling, multivariate probit, simple probit, and robust ordinary least square models were used for analysis. Results showed that agricultural productivity and sustainable water supply significantly influence water conservation. Water accessibility significantly influences participation in water conservation and environmental sustainability, while government regulations influence water accessibility. Determinants of water conservation practices include water quality, education, occupation, water proximity, and residence location. Probit and robust ordinary least square models showed that earth dams significantly increase food security and income, while water banks and guttering significantly influence food security and income. Water tanks were the most preferred water conservation practice, followed by rooftop catchment systems. The study recommends that policymakers prioritize investing in water infrastructure and encourage households to participate in water resource conservation to ensure sustainability and benefit societal development. The study highlights the urgent need for comprehensive and inclusive water management strategies to address water scarcity, especially in rural areas. It emphasizes the importance of understanding rural residents' behaviors regarding water accessibility and conservation to inform targeted policies and initiatives for sustainable water management and rural livelihoods.