Unsafe water is continuing a factor influencing to population health, especially child health worldwide. In Vietnam asseccibility to safe water of population and school students is still limitted. Parents who have good knowledge, attitude and practices in safe water can contribute significantly to improve accessibility of safe water for their child. Objective: To describe knowledge, attitude, practice in safe water among parents of secondary school student in Bavi district, Hanoi in 2013. Method: A descriptive cross-sectional study was carried out. Parents of secondary school student were interviewed directly. Results: 81.2 percent of parents perceived that pipe water is safe water source. 1.9 percent of parents still believed that surface water such as river or pond water is safe water source. 89.9 percent of parent answered that safe water is clear. 19.6 percent of them reported that safe water was clear and free from harmful microorganism and substances. Main water sources of households were dug well (49 percent), borehole (31 percent), pipe water (10 percent) and rain water (8 percent). Natural sedimentation was applied among 52.2 percent of households for treating water, filter was second common method which was used (49.2 percent). 11.9 percent of households used alum to treat water. 8.6 percent of households did not treat water. Conclusion: Communication about safe water and water treatment methods should be carried out in order to improve practice/access to safe water of population as well as students which contribute to achieving the Millennium Development Goals.