Purpose The purpose of this study was to investigate the effect of gait velocity on the correlation of the muscle activation of the lower limbs and between each muscle. Methods Participants were adult female college students (n = 20) who could walk normally. Subjects first measured the MVIC (Maximal Voluntary Isometric contraction) after attaching the electrodes to the gastrocnemius medialis, gastrocnemius lateralis, soleus, tibialis anterior. Thereafter, treadmill exercise was performed to measure muscle activation during gait. The velocity of the treadmill was set to 0, 2, 3.5, and 6 (km/h). Results As a result, according to the increase in gait velocity of the treadmill gait, the muscle activation of the lower limbs has also increased. In addition, as a result of confirming the correlation between the muscles involved in gait under each velocity condition while gait velocity and muscle activation increased proportionally, the tibialis anterior located in front of the tibia showed a lower increase in muscle activity than gastrocnemius medialis, gastrocnemius lateralis, and soleus but gastrocnemius medialis showed a higher increase in muscle activation than gastrocnemius lateralis. In addition, at the only standing position at 0 km/h, the tibialis anterior showed a higher increase in muscle activation than gastrocnemius lateralis. Conclusion The regulation of gait velocity seems to be able to relatively increase muscle activation of the lower limbs as well as muscle activation of a particular muscle.