The increasing prevalence of obesity is a global health problem (WHO, 2013). Childhood obesity and decreased fitness are risk factors for chronic diseases. Previous research indicated that childhood obesity and fitness levels are negatively related (Aryana, 2012; Chi, 2014). PURPOSE: The purpose of this study was to determine the relations between obesity and measures of fitness in Chinese children. METHODS: A total of 457 Chinese students (54.5% male, 45.5% female) from grades 1 to 3 (age in years: 9.2 ± 0.89) were tested by physical education teachers in Shanghai, China. The tests included 50 Meters Run, Jump Rope, Sit and Reach, Pull up/Push up (only tested in grade 3) that separately reflected explosive force, coordination of upper and lower limbs, flexibility, muscular strength and endurance, in which Pull up/Push up was separately tested for males (pull up) and females (push up). Based on Chinese standards, for all tests students were classified into four categories, Excellent, Good, Pass and Fail. Height and weight were measured and obesity status was classified as normal, overweight and obese using BMI cut-points. Results: The 50 Meters Run (r = 0.141, p < 0.05), Jump Rope (r = -0.158, p < 0.01), Pull up/Push up (r = -0.380, p 0.05). The Chi-square test was conducted to analyze the relations of fitness and obesity classifications. Obesity status was significantly related to the 50 Meters Run (χ2 = 36.94, p < 0.01), Jump Rope (χ2 = 20.70, p < 0.05) and Pull up/Push up (χ2 = 30.66, p < 0.01), but not the Sit and Reach (χ2 = 8.75, p > 0.05). The %fitness classification of Fail increased across normal, overweight and obese classifications for the 50 Meters Run (11.2% to 41.5%), the Jump Rope (5.0% to 9.8%) and the Pull up/Push up (2.0% to 26.7%). CONCLUSIONS: Performance on the 50 Meters Run, Jump Rope and Pull up/Push up was significantly related to obesity. Higher values of BMI and classified obesity status of Chinese children were related to poorer performance on some components of fitness. Future research on school based interventions to increase physical activity, improve fitness and decrease obesity would serve the public health of China.