The objective of this paper was to evaluate the quality of breast muscles and leg muscles of slowgrowing, 14-week-old chickens representing the two native breeds: Rhode Island Red and Greenleg Partridge. The technological parameters tested were: breast and leg muscle acidity 24 h (pH_24h) post mortem; colour according to L*a*b* (CIELAB 1976); drip loss after 24 h of muscle storage at +4°C; thermal loss after muscle cooking; breast muscle tenderness based on measurement of peak shear force (WamerBratzler). The results were statistically analysed using a variance analysis and a Duncan’s multiple range test. The study showed an effect of slow growing chicken breed on meat quality. As for the Greenleg Partridge breast muscles the following parameters were found characteristic: a more intensive colour, a greater water holding capacity, a more favourable pH, and a higher tenderness. The effect of chicken breed on leg muscles quality referred solely to their colour.