An experiment was carried out on 540 Hisex Brown laying hens (35 weeks of age) whose design consisted of two factors and 5 replicates. The first factor was Mn (0, 80, 120 ppm) and the second was Zn (0, 40, 60 ppm). Results showed that egg production was highest for the Mn120 treatment (90.62%) and lowest for the control (84.51%) (P<0.05). Broken egg percentage was lowest for the Mn120 treatment (1.24%) and highest for the control (4.71%) (P<0.05). The yolk proportion of the Mn80 treatment

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... %) was the highest and the control was the lowest (24.76%) (P<0.05). Haugh unit and eggshell quality were also higher than those of the control (P<0.05). Regarding Zn factor, the highest egg production was in the Zn40 treatment (89.48%). Broken egg percentage in the Zn40 and Zn60 treatments decreased (2.46%) as compared with that in the control (3.56%). Egg quality parameters were also higher than those of the control (P<0.05). Interaction between Mn*Zn showed that broken egg percentage was the lowest in the Mn120*Zn60 (0.91%) and the highest in the control (6.93%). Egg quality was also improved when adding Mn and Zn into the diets. Feed consumed per egg (g/egg) was significantly lower (P<0.05) when adding both of Mn and Zn for laying hens.