The purpose of this study was to investigate visual control of dynamic balance in children. 24boys as subjects consisted of six (n=12), eight(n=12) years old in elementary school. They walked the balance beam under all the task conditions(4) in a heel-to-toe fashion. The task conditions was body/environment condition, body condition, environment condition, full visual condition. Each of child was given three practice trials walking the beam in fully lighted room . The average of three test trials under each of condition was the dependent variable. The results were as follows: The first, the effect of task condition was significant (F(3, 66)=65.05, P<.001). Second, the effect of year was significant (F(1, 66) =571.9, P<. 001) . Third, the interaction between age and condition was also significant(F(3,66)=32.40,P<.001) . And, SNK procedure test (post hoc) indicated significant difference between age and task condition (P< .05) . In conclusion, development of sensory-motor control in children is significantly related to dynamic balance. Also, there may be a trend away from the need to visually monitor body/ environment relationships to maintain effective balance (six years old) to a shift toward greater reliance of vestibular-proprioception information for maintaining dynamic balance control at eight years old .