Actinic keratosis is a frequent disease of older ages. It may transform into a squamous cell carcinoma. An important approach for prevention is sunscreen. The effect of a standardized and individualized sunscreen education is examined in this retrospective analysis. 332 patients with actinic keratosis were asked to take part on a sunscreen education, which was repeated after three, six and twelve months. They were requested to fill in a questionnaire before each consultation. The results showed several faults in knowledge and execution of sunscreen within the investigated patient collective. The sunscreen education was proper for improving the following issues. The patients felt safer in dealing with the sunscreen and performed it more often. Many mistakes in the execution of sunscreen were corrected. There is more need for education in the difference between UVA and UVB radiation and the choice of the appropriate sun protection factor. Recommendations concerning advisable clothing and headgear were not applied by the patients. Some advised behaviours didn't provide significant improvements before multiple repetitions. The standardized sunscreen education is an easy to use and effective instrument to improve sunscreen behaviour at older ages. Knowledge and execution of sunscreen can be improved. The decisive factor for success is the repetition.