The study focused on assessing the effect of nurse-led deep vein thrombosis prevention training on patients' knowledge and self-care practices. Forty patients participated in this quasi-experimental study. Participants were trained by the guidebook prepared by the researchers before the surgery. Data were collected with Autar Deep Vein Thrombosis Risk Assessment Scale and questionnaires before and after the training. The questionnaires were prepared by the researcher. Data were evaluated with Mann-Whitney U, Wilcoxon, Kruskal-Wallis variance analysis, significance of difference test between two means, and one-way variance analysis tests. The average deep vein thrombosis knowledge score was 0.1 +/- 0.5 over 54 before the training, whereas it was 20.2 +/- 5.7 after the training, and there was a statistically significant difference in patients' deep vein thrombosis knowledge scores after training period (P = .000). Patients performed an average of 8.8 out of 13 protective self-care practices during the postsurgery period. The majority of the patients were satisfied with the training. The training provided by the nurse contributed to the fact that the patients had knowledge about their own health problems and took responsibility for self-care. We have not been able to increase the awareness we want on some groups such as those older than 52 years. Other studies should be carried out, especially in these groups, with different training methods.