To study the efficacy of Newcastle disease and infectious bursal disease vaccines in chickens infected by cryptosporidium, 280, seven days old chicks were used and divided into 14 groups. Chickens were vaccinated with live or inactivated Newcastle disease vaccines and live or inactivated Gumboro disease vaccines or both vaccines. Random blood samples were collected for four weeks post vaccination for investigation of humoral immune response against Newcastle disease vaccine by the haemagglutination inhibition (HI) test, and by serum neutralization and agar gel precipitation tests for Gumboro disease vaccine. Investigation of the cellular immune response was carried out using lymphocyte transformation test for both Newcastle and Gumboro disease vaccines and delayed hypersensitivity for Newcastle disease vaccine only. Significant difference was found in both humoral and cellular immune response between groups that infected and vaccinated either with Newcastle or Gumboro disease vaccines or both compared to the control groups that vaccinated only. From the obtained results, the following recommendation should be put in consideration : (1) Rearing the birds in good hygienic measures, (2) Faecal examination of the birds specially for cryptosporidium before vaccination.