PROBLEM TO BE SOLVED: To provide a production method of slow-release compact that includes an agent and a polyglycolic acid based resin and expresses agent slow-release under the existence of moisture.SOLUTION: A production method of a slow-release compact includes: a pretreatment in which a polyglycolic acid based resin in which a calorie &DgrHat a crystallization temperature Tc measured by a differential scan calorimeter under the nitrogen atmosphere, and in a temperature rising process of a rate of temperature rise of 20°C/minute is at least 1 J/g is prepared a mixing process in which the polyglycolic acid based resin obtained by the pretreatment and an agent are mixed and a molding process in which a mixture obtained from the mixing process is performed by compression molding at a temperature T that satisfies a condition represented by the following formula(1): Tg&leT
