Colour changes in Biceps femoris, Rectus femoris and Pectoralis major broiler chicken muscles were determined with a reflectance colorimeter after irradiation with gamma ⁶⁰Co rays. The muscles were irradiated with doses of 2, 3, 5, 7 and 10 kGy. The colour parameters L*, a* and b* were measured after 2, 5, 7 and 9 days of refrigerated storage of muscles at 1^oC (±0.5^oC) using a MINOLTA CR-200b reflectance colorimeter. The saturation of colour C* was also calculated and the significance of redness and yellowness effect on saturation was estimated by a linear regression analysis. Only in the Biceps femoris muscle were all the examined colour parameters found to be dependent both on storage time and irradiation treatment, however, the relationship between the dose and the measured effect demonstrated no linear characteristics. It was noted that the difference between the irradiated and control Biceps femoris muscles resulted from different trends of L*, b* and C* changes during storage. The values of partially standardised regression β coefficients for C* as the linear function of a* and b* revealed that in all examined muscles, a more important contribution to saturation was noted for the redness a* in the irradiated samples, whereas the yellowness parameter b* appeared to be more important in the control, non-irradiated samples. That finding was in accordance not only with reports in the literature but was also confirmed by the visually observed pink hue of muscle colour after irradiation.