Objectives: This study investigated the associations between gait velocity and kinematic variables in the first half of the gait cycle according to stroke severity. We performed gait analysis in individuals with stroke, focusing on changes in the center-of-gravity (COG) position on the paretic side in the first half of stance phase.Methods: Gait data of 80 individuals (20 each in Brunnstrom recovery stage: III, IV, V and VI) with stroke acquired using a 3D motion analysis system was retrospectively analyzed. Associations of gait velocity with the COG positions in the anteroposterior directions and vertical increases in the first half of stance phase on the paretic side were compared according to stroke severity, using correlation analysis.Results: Gait velocity showed strong positive correlations with step length on the paretic side at initial contact, the rate of vertical increase in the COG during single-leg stance, and the proportion of single-leg stance time in the gait cycle. The associations between velocity and each kinematic variable differed according to stroke severity. Gait velocity was strongly correlated with the rate of vertical increase in the COG during single-leg stance and the proportion of single-leg stance in severe hemiplegia, while a strong correlation was observed with step length on the paretic side in mild hemiplegia.Conclusion: An upward shift of the COG during single-leg stance was an important factor in gait velocity, and the correlation between gait velocity and the rate of vertical increase in the COG during single-leg stance was stronger when hemiplegia was more severe.