An on – farm experiment was conducted at Binh Yen Hamlet, Long Hoa Village, Cantho Province in the South of Vietnam. A total of 60 Tam Hoang (TH) and 60 Tau Vang (TV) layers were equally divided between 6 small farms (10 TH and 10 TV on each) and were followed for 20 weeks of the laying period. The hens were allocated at random to 2 treatments in a 2 * 2 factorial experiment. The first factor was breed (Tam Hoang and Tau Vang), and the second factor diet, including: Mixed diet including maize meal, fish meal and roasted soya bean meal and with a supplement of oyster meal and bone meal; Separate diet, including the same feedstuffs but supplied separately in 3 feeders, and with oyster and bone meal mixed together with the maize meal. There were thus 4 treatments with 6 replications (farms) and with 5 birds per experimental unit (pen) and in total 20 hens per farm. Daily dry matter (DM), crude protein (CP) and metabolisable energy (ME) intakes were 21 % higher for the improved Tam Hoang hens compared with the local Tau Vang hens. The hen–day production and mean egg weight were significantly different between breeds (Pthe Tam Hoang were 30.1 % and 43.5 g respectively, compared with 23.9 % and 39.2 g, respectively, for the Tau Vang. However, there were no significant differences between treatments, and for the mixed and separate diets hen-day production and egg weights were 27.2 % and 41.4 g compared with 26.8 % and 41.4g, respectively. The feed consumption per kg eggs was not significantly different for both treatments and breeds. In addition, CP and ME/kg eggs were not significantly different between breeds, but were between treatments. CP and ME intakes were 602 and 633 g/kg eggs and 50.8 and 52.6 MJ/kg eggs for the Tam Hoang and Tau Vang hens, respectively (P>0.05). For the mixed and separate diets, CP and ME intakes were 681 and 553 g and 49.8 and 53.6 MJ / kg eggs, respectively (Pseparate diet can get around 41 % and 44 %f the CP, 42 % and 35 % of the ME intakes (respectively) from the scavenging feed resource.