Abstract: Effects of magnetized water irrigation on growth and physiological characteristics of tomato during seedling stage and flowering stage were studied by means of solar greenhouse experiment.Two treatments were designed，including magnetized water irrigation and ordinary water irrigation（CK）.Results showed that，compared with ordinary water irrigation，for tomato used magnetized water irrigation treatment，plant height growth was 15%，stem diameter growth was 8.2%.Magnetized water irrigation treatment had no significant effect on chlorophyll content in seedling stage and flowering stage of tomato leaves.The SOD，POD，CAT activity growth of tomato seedling stage leaves after treatment of magnetized water irrigation was 22%，44.4% and 18.4% respectively，the SOD，POD，CAT activity growth of tomato flowering stage leaves after treatment of magnetized water irrigation was 15.8%，21.5% and 48.3% respectively.Growth of root activity of tomato in flowering peniod after irrigated with magnetized water was 56%.Magnetized water irrigation could effectively improve grow performance，enzyme activity and root activity of tomato，which could provide reference for application of green，pollution-free vegetables production technology.