The effect of cooking on pH, juiciness, instrumental colour and microstructural properties of chicken breast meat was investigated. Industrial skinless chicken breast meat samples were purchased, frozen and sliced into dimensions , thawed and cooked by air frying (AF), baking (BK), deep fat frying (DF) and grilling (GR) at 170, 180 and 1900C for 0, 4, 8, 12 and 16 min. The pH value of the cooked samples increased from 6.05 to 6.25. Cooking methods, temperatures and times each resulted to increase in pH. The results of objective sensory instrumental analyses showed that cooking decreased significantly (p < 0.05) juiciness of cooked chicken breast meat. Samples cooked by BK had the highest juiciness value of 24.91%, while DF cooked samples had the least value of 13.89%.The instrumental analyses increased L*, a*, b* values and browning index. The temperature and time of cooking showed similar effects on juiciness and instrumental colour. Short cooking time (8 min) and 1700C resulted in higher juiciness and best appetizing appearance to the consumers. The microstructure studies showed that raw chicken breast meat had an intact muscle fibres and bundles, but cooking caused disintegration of muscle fibres, perimysial – collagen shrinkage and it resulted to drier samples with big cracks/ voids and big surface damages, particularly in AF, BK and GR cooked products at 1900C for 8 min.