Early childhood obesity is a serious worldwide problem, and fundamental movement skills (FMS) are very important factors in human movement. Thus, several advanced studies have examined the associations between FMS and body mass index (BMI). The purpose of this study was to investigate BMI and FMS (locomotion and object control skills) in Korean preschool and to explore correlations between FMS and BMI. A total of 216 preschoolers, including five-year-olds (47 boys, 62 girls) and six-year-olds (55 boys, 52 girls), participated in this study. FMS were measured using the Test of Gross Motor Development-II (TGMD-II), and BMI was calculated as the weight (kg) divided by the square of the height (m) [weight/ height[superscript 2]]. The results indicated that the children's FMS (locomotion and object control skills) did not correlate with their BMI levels. In addition, most of correlation coefficients between BMI and locomotion skills, as well as correlation between BMI and object control skills were not significant. These results suggest that the motor abilities of the FMS do not differ between healthy-weight and obese preschoolers. If teachers incorporate a physical activity (PA) program that focuses on FMS, they must consider other aspects, such as exercise intensity and the regulation of food intake, in the organization of an FMS program for obese children.