The study was carried out to determine the effect of organic acid mixture (Poulacid) supplementation in the diet to commercial diet on performance and egg quality of laying hens. 400 Isa Brown laying hens at the 21 weeks of age were randomly distributed in a completely randomized design experiment, with 4 treatments and 25 replicates (each replicate consisted of 4 birds/pen), and the experimental data was collected in 10 weeks. Treatments used: PA0: Basal diet + 0% Poulacid in diet (control); PA0.1: Basal diet + 0.1 % Poulacid;  PA0.15: Basal diet + 0.15 % Poulacid; PA0.2: Basal diet + 0.2% Poulacid. The results showed that no effect of poulacid on feed intake, egg weight and egg mass, but a little improvement hen day production and feed conversion ratio in 0.1% and 0.15% diets compare to control and 0.2 % groups. The 0.15 and 0.2% poulacid supplement diet showed lower proportion of broken, unnormal and double york eggs compared with control group. There were no significant effect of treatments on egg shape index, shell weight, shell thickness, albumen weight, Haugh Unit, yolk weight. But there was a light improvement of albumin index and yolk color in supplemented groups compared with control group. The conclusion of this experiment is adding Poulacid product at 0.1% could lightly improve hen day production, feed conversion  ratio but without egg quality of commercial laying hens.