The results showed that the risk factors of myopia in secondary school students were: over 2 sessions per day (OR = 1, 653; CI 95%: 1.115 - 2.450, p < 0, 05); sitting far away and not seeing clearly the board (OR = 2, 683; CI95% là 1.588 - 4.532; p < 0, 05); incorrect bowing posture (OR = 1, 413; CI 95% là 1.018 - 1.962, p < 0, 05).