We examined the role of cardiorespiratory fitness (CRF) on the association between physical activity (PA) and abdominal fat content in adolescents. Abdominal fat content was measured by waist circumference, waist-to-height ratio and dual energy X-ray absorptiometry (DXA) at 3 regions (R1, R2, and R3). PA and CRF were assessed by accelerometry and the 20 m-shuttle run test, respectively. Vigorous PA was inversely associated with waist circumference and waist-to-height ratio (beta from -0.149 to -0.197; p < 0.05). In both CRF groups (i.e., low and high), vigorous and moderate-to-vigorous PA (also average PA in the low CRF group) were inversely associated with abdominal fat (i.e., R1, R2 and R3; beta from -0.146 to -0.244; p < 0.05). This association did not differ according to CRF group (P for interaction >0.05), yet the percentage of variance in abdominal fat content, when assessed by DXA, explained by PA was slightly higher in adolescents with low CRF (3-8%) compared to those with high CRF (2-4%). The findings indicate that there is not a clear interaction effect of CRF in the association between PA and abdominal fat in adolescents, yet slightly stronger association was observed in the low fit group.