OBJECTIVE: To synthesize 3-hydroxyadamantane-1-carboxylic acid and optimize its synthesis technology. METHODS: Using 1-adamantane carboxylic acid as starting material, triethyl benzyl ammonium chloride (TEBAC) as phase transfer catalyst, 3-hydroxyadamantane-1-carboxylic acid was prepared by potassium permanganate in alkaline condition. Treating yield rate as index, central composite design-response surface method was conducted to optimize the reaction temperature, reaction time and the mole ratio of potassium permanganate-substrate. RESULTS: Optimized synthesis technology was as follows as reaction temperature 60 ℃, reaction time 8.5 h, mole ratio of potassium permanganate-substrate 1.28 ∶ 1. The deviation for yield rate of prediction value and the measured value was 1.38% (prediction value was 91.26%, the measured average value was 93.61%, n=6); the average purity of prepared 3-hydroxyadamantane-1-carboxylic acid was 99.26% (n=6). CONCLUSIONS: 3-hydroxyadamantane-1-carboxylic acid with high purity and yield rate is prepared successfully by optimized synthesis technology.