A method for synthesizing cis-3, 3, 5-trimethylcyclohexanol (cis-3, 3, 5-trimethylcyclohexanal), a drug intermediate of cyclonsil, is carried out according to the following steps: A. Add 1,5, 5-trimethylcyclohexene -3-one (2)0.51mol and 600ml of 2-amino -5-chlorobenzoic acid solution with a mass fraction of 37% into a reaction container, reduce the temperature of the solution to 0 ℃, and control the stirring speed to 110rpm; B, slowly add 1.38mol of lithium powder, control the addition time to 120min, continue the reaction after adding 90min, then slowly raise the temperature to 16 ℃, and control the heating process to 50min; C, the solution is concentrated under reduced pressure, the concentrated solution is added to 230ml of potassium bromide solution with mass fraction of 28%, and 100ml of oxalic acid solution with mass fraction of 38% is added, the dimethylamine solution with a mass fraction of 57% was extracted for 7 times, and the extracted solution was combined. The extraction solution was washed with an ethyl acetate solution with a mass fraction of 48%, the butanone solution with a mass fraction of 60% was washed, the calcium chloride dehydrating agent was dehydrated, the fraction at 1.7kPa was distilled under reduced pressure, the fraction at 80-86 ℃ was collected, and recrystallized in a cyclohexane solution with a mass fraction of 88% to obtain crystals cis -3,3, 5-trimethylcyclohexanol (cis, 5-trimethylcyclohexanal) 64.45g, 89% yield.