The process for preparing 2-amino-6-iodopurine including the steps of suspending at least one chloropurine compound selected from 2-formylamino-6-chloropurine, 2-formylamino-6-chloropurine acetate and 2-amino-6-chloropurine in a solution comprising aqueous hydriodic acid and an alkyl ketone having 3 to 7 carbon atoms; and stirring the resulting suspension at 0.degree. to 50.degree. C. According to the process of the present invention, 2-amino-6-iodopurine can be simply, industrially, and advantageously prepared.