Introduction: Difficulties are perceived with respect to management of the nursing care process by nursing interns, which limits its application and puts quality of care at risk. Objective: To assess the effectiveness of a training received by interns concerning knowledge and application of the nursing care process. Methods: One-group pretest-posttest pre-experimental study carried out in 2018 at the National Maternal and Perinatal Institute. The population and the sample were 78 and 60 nursing interns, respectively. After the pretest, training was planned and carried out, every four weeks, with twelve groups of five interns each. Then posttest was applied. The Smirnov-Kolmogorov test determined the normality distribution of the data and, according to the variables and observation time, descriptive statistics was applied. Transforming the vigesimal scores into the categories disapproved, fair, good, very good and excellent, the final value of the variables was obtained. The hypothesis test was performed using Student's t test for means of two paired samples. Results: The mean age was 24 years. 86% (52) were female. The scores before the intervention were 10.6 ± 1.45 for knowledge and 13.7 ± 1.21 for application. For the posttest application of the nursing care process, such scores were 16.4 ± 1.57 and 17.2 ± 1.64, respectively. Conclusion: The effectiveness of the program was demonstrated by the positive level variation in knowledge about the nursing care process, being from regular to very good. In the application level, it moved from the level regular to good and excellent.