A new open-circuit respiratory calorimetry apparatus with 12 chambers in parallel for poultry was used to determine the net energy requirement for maintenance for different chicken breeds, in order to explore the differences in energy metabolism among them. Thirty-five-week-old Hy-Line brown laying hens, 32-week-old Jilin-Luhua hens and 25 to 28-day-old Ross 308 broilers were chosen, and 24 chickens per breed were needed. A completely random trial was designed. Twelve replicates were set for each breed of test chickens, with 2 chickens per replicate. Each kind of test chickens were raised in a separate house and individually fed complete feed that met their nutritional needs. The pre-feeding period was 7 days, and formal trial period was 21 days which included 3 phases, with 9 days each phase. In each phrase, 8 chickens from each breed were randomly selected. After weighing, each 2 chickens were placed in the metabolic chamber of the respiratory calorimeter apparatus, and each 4 metabolic chambers corresponded to one kind of chickens. Then the gas exchange was measured in the metabolic chamber for 9 days of formal trial period, including 3 days of dietary adaptation period, 3 days of respiratory calorimetry and 3 days of fasting heat production. The results showed that the metabolic body weight of Hy-Line brown laying hens and Jilin-Luhua hens was significantly lower than that of Ross 308 broilers (P<0.05). The fasting heat productions under the metabolic weight of Jilin-Luhua laying hens and Ross 308 broilers was significantly higher than that of Hy-Line brown laying hens (P<0.05). For heat increase consumption (HI) under metabolic body weight, feed intake respiratory quotient (RQ), and fasting RQ, the differences among the three kinds of chickens were not significant (P>0.05). The maintenance net energy requirements of the 34-week-old Hy-Line brown laying hens, 31-week-old Jilin-Luhua hens, and 25 to 28-day-old Ross 308 broilers are 368.79, 449.24 and 450.75 kJ/(kg BW^0.75·d), respectively.