The objective of this research was to evaluate the inclusion of two qualities of Mexican oregano oil (MOO) in broiler diets on broiler weight, feed intake, feed efficiency, average daily gain, and water intake. The qualities were MOO1 (4% thymol, 60% carvacrol) and MOO2 (40% thymol, 20% carvacrol). Nine treatments were prepared by the combinations of MOO1 + MOO2 (0, 400, and 800 mg kg−1; added per kg of feed) respectively: 0+0, 0+400, 0+800, 400+0, 400+400, 400+800, 800+0, 800+400, and 800+800. Eighteen chicks per treatment were divided in a completely randomized design into nine cages. Broiler weights were altered by the treatments at 21 d, when 400+400 had the highest weight, and on day 39, when the greatest weight was seen in broilers on treatments 800+0 and 800+400. Feed intake was affected by treatment on day 39, with broilers on 800+0 exhibiting the highest values. Water intake was influenced by the treatments on days 14, 21, 35, and 39, when 0+0 represented the lowest. Feed efficiency was altered by the treatments on days 14, 28, 35, and 39, whereas average daily gain was affected from days 14 to 39. Supplementation of Mexican oregano oil has beneficial effects on broiler weight, feed efficiency, average daily gain, and feed and water intakes. Combinations of thymol and carvacrol levels have varying effects on these parameters. The higher relative body weights of groups 400+0, 800+0, and 800+400 suggest positive market value effects of these combinations of Mexican oregano oil.