The invention discloses a compound orlistat nano-emulsion oral liquid which contains the following components by mass percentage: 35%-45% of surfactant, 0-1% of cosurfactant, 0-1% of oil phase, 0.5%-4% of orlistat, 0.5%-3% of fructus cannabis oil, 0.5%-2% of evening primrose oil, 0.1%-0.5% of beta-carotene, 0.0001%-0.002% of vitamin D, 0.1%-0.5% of vitamin E, 0.0001-0.002% of vitamin K, and the balance of deionized water, and the sum of the mass percentage of the components is 100 percent. Aiming at the features of obese patients, the compound orlistat nano-emulsion oral liquid has multiple effects of reducing absorption of fat and heat in food, accelerating consumption of stubborn brown adipose tissues accumulated in the body, replenishing micronutrient matters lost during weight loss, reducing blood fat and cholesterol and the like, and does not have the side effects of insomnia, strength lack, palpitation and the like.