This study was performed on the 97 children (42 females and 55 males, mean age 11.44±1.68) with stable alleigic asthma at the Pediatrie Allergy Polyclinic Unit, Çukurova University. Asthmatic children were divided into three groups. Groups A was comprised of 35 children with a sedentary life-style who avoided even free play, group B of 35 children who engaged in free play, and group C of 27 children who participated in a regular swimming program of three months duration. The 50 normal control subjects, were divided into two subgroups: Groups D was comprised of 25 children with normal activity level, group E of 25 children who participated in organized sports. Physical work capacity (PWC170) was assessed by a continuons graded test on a bicycle ergometer; and pulmonary function tests were determined by a spirometer. Aim of investigation: To determine the pulmonary functions and exercise capacity of various degrees of physical activities of allergy related asthmatic children. Group A,B, C compared to group D, E; and groups A and B compared to group C showed, significant differences (p<0.01) in PWC170, FEV1 (forced expiration volume 1 second) VC (vital capacity), PEF (Peak Expiratory Flow), MVV (maximum volunter ventilation) measurements. These data suggest that, physical fitness of asthmatic children is low and it can be potentially increased with regular physical activity.