Cancer is a condition that occurs due to abnormal growth of cells in the body. One of the compounds that potentially developed as anticancer agent is Gamavuton‐0 (GVT‐0). GVT‐0 is a curcumin’s analog compound. This compound can be synthesized by a reaction of one mole of acetone and two moles of vanillin as starting materials using acid or base catalyst. The main purpose of this research is to determine the best concentration of the acid catalyst for the synthesis of GVT‐0. Synthesis was carried out in the round bottle flask with heating. The dissolved of 4.14 gram of vanillin in ethanol was mixed with one milliliter of acidified acetone. The concentration of acid catalyst (HCl) that was used is 2 ppm, 4 ppm, 6 ppm, and 8 ppm of acetone, respectively. The heating was conducted for 1.5 hours and then let it cool in the refrigerator for overnight at 1‐10 ⁰C. After that, the purification process can be conducted. In this purification, the hot water maceration method was used. In the finding of the best concentration of acid catalyst, the mathematical and statistical Stratigraphic Centurion 15 software was used. The analysis that was used in this research