The objective of this study was to characterise and compare the quality of the MSMs obtained from carcasses from breeding and laying hens to provide useful information for the processing industry. The composition of the mechanically separated meat (MSM) varied between the two groups. Laying hens contained the most crude protein (P<0.05) and high ash content (P<0.05). Calcium concentrations and bone contents were higher (P<0.05) for laying (448 mg/100 g and 1.25%, respectively) than for breeding hens (299 mg/100 g and 0.78%, respectively). Levels of unsaturated fatty acids for laying and breeding hens (75.89 and 72.82%, respectively) and cholesterol concentrations (73 and 61 mg/100 g, respectively) were higher (P<0.05) for laying hens than for breeding ones.