Introduction: Cerebral palsy (CP) is considered one of the commonest causes of childhood disability. Pulmonary dysfunctions is one of the important causes of morbidity and mortality specially in moderate to severely affected children of cerebral palsy. Aims: This study has been designed to evaluate and compare the pulmonary function parameters ofchildren with spastic diplegia and spastic hemiplegia cerebral plays by spirometry testing.Settings and Design: Cross sectional comparative study was done at Physical Medicine and Rehabilitation department of tertiary care centre of North India. Methods and Material: Nineteen children with spastic diplegic CP and 18 children with spastic hemiplegic who satisfy the exclusion criteria were recruitedand pulmonary function parameters was evaluated with the help of computerised spirometer and compared in terms of Forced Vital Capacity (FVC), Peak Expiratory Flow (PEF), Vital Capacity (VC), Forced Expiratory Volume in 1st second, FEV1/FVC, Tidal Volume (TV), Expiratory Reserve Volume (ERV) and Inspiratory Reserve Volume (IRV). Results: Children with spastic diplegia have statistically significant lower FEV1, FVC, PEF and VC and no significant difference in ERV, IRV and TV. Conclusions: Cerebral palsy children may demonstrate compromised pulmonary function and it is more compromised in spastic diplegic group compared to hemiplegic CP children. Early clinical Assessment in these children with prompt intervention of therapy should be considered.