Objective To observe the clinical effect and safety of different concentrations of aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of actinic keratosis (AK). Methods From June 2021 to May 2023, 48 patients with AK admitted to Baoshan People's Hospital were selected as the research subjects, and they were randomly divided into control group and observation group, with 24 patients in each group. Both groups were treated with ALA-PDT, the control group was treated with 10% concentration solution, and the observation group was treated with 20% concentration solution. The clinical efficacy, adverse reaction rate and pain degree score were compared between the two groups. Results The total effective rate of treatment in the observation group was 91.67%, which was higher than 66.67% in the control group (P <0.05). The incidence of adverse reactions in the observation group was 12.50%, which was lower than 45.83% in the control group (P <0.05). After 4, 12, and 48 weeks of treatment, the VAS score in the two groups was lower than that before treatment, and that in the observation group was lower than that in the control group (P <0.05). Conclusion Compared with 10% concentration solution, 20% concentration solution of ALA-PDT can enhance the treatment effect of AK, reduce the degree of physical pain, and have higher safety.