The invention discloses a method for producing a wet strength agent. The method comprises the following steps: A) mixing a polyamide polyamine epichlorohydrin solution, sodium dodecyl sulfate, linolenic acid, mono lauryl phosphate potassium, polyethylene polyamine, sodium sulphamidate and propylene glycol, and stirring a mixture for 2-3 hours; B) adding water in the above stirred mixture for mixing at the temperature of 85-95 DEG C, homogenizing the material in a homogenizer for 3-5 hours at the temperature of 65-85 DEG C; and C) after homogenizing, cooling a solution to room temperature , dropping a pH conditioning agent to prepare the wet strength agent. By employing the above method, various components are fully mixed and reacted, reasonable components are added during a production process, the stability is good, harmful substance is not generated during the production process, environment pollution and damage on human body can be avoided, production cost is reduced, reaction temperature and time can be controlled in the reasonable mode during the production process, so that the paper quality can be increased.