Introduction: Low levels of moderate and vigorous physical activity are a factor of important behavioral risk in the obesity in children. Objective: The objective of this study was to determine the nutritional status and physical condition of students, by comparing the results obtained by gender, obesity, and physical performance. Material and methods: 578 students; 308 men of 11.22 ± 1.93 years and 270 women of 10.93 ± 1.92 years, participated in the investigation. Were evaluated; body mass index (BMI), percentage body fat (%FM), contour waist (CW), waist-to-height ratio (wtHR) and physical performance according to the test of the National Study of Physical Education of the Agency of Quality of Education of Chile. Results: The %FM was higher in women (p < 0.001). In the Test of abdominal and Navette performance was higher in men and in the test of fl exo-extensions of arm performance was higher in women (p < 0.05). Category of obese schoolchildren showed lower results in the test: abdominal, long jump, fl exo-extensions of arm and Navette (p < 0.001). The VO2MAX was lower in the overweight subjects (p < 0.001). The students who need to improve 3 or 4 test presented more wtHR (p < 0.001) and %FM (p < 0.001). There is a negative association between the wtHR and the VO2MAX (-0.543, p < 0.001). Conclusions: There exists a high predominance of excess weight and obesity, also it is appreciated a low physical performance associated with this condition. The students, who need to improve 3 or 4 test of physical condition, have a higher average of %FM and wtHR, this last variable is a powerful indicator of cardiovascular risk.