Unsystematic household waste management in water villages could have adverse effects on the surrounding marine ecosystem. This study is conducted to evaluate the knowledge and practices regarding household waste management in Tanjung Aru Water Village, Sabah, Malaysia. Using a survey approach, data was obtained from the use of a guided questionnaire administered to 62 respondents. The average score of knowledge is 8.35 ± 1.73 which is moderate while the highest average percentage for practice is 57.3% which is the good practice. The contributing factors to household waste mismanagement in this area were the knowledge and practices of the villagers, and the ineffective household waste management system. The implication of this research is that the waste management system should be tailored to the nature of the settlements. Future waste management system should incorporate effective household waste system, intensive monitoring and enforcement, continuous education on household waste management, property tax and community engagement.