Central venous catheters (CVCs) are frequently used, but the rate of complications is high. This study evaluates the effects of a short training program for CVC insertion in a university-based teaching hospital. A sample of adults with CVCs inserted outside the intensive care unit was selected from two academic years: 2015, year without structured training, and 2016, year with structured training. Clinical and laboratory information, as well as the procedure’s characteristics and complications (mechanical and infectious) were collected. The incidence of complications before and after the training was compared. A total of 1502 punctures were evaluated. Comparing the pre- and post-training period, there was an increase in the choice for jugular veins and the use of ultrasound. A numerical reduction in the rate of complications was identified (RR 0.732; 95% CI 0.48–1.12; P = 0.166). This difference was driven by a statistically significant lower rate of catheter-related infections (RR 0.78; 95% CI 0.64–0.95; P = 0.047). In the multivariate analysis, aspects regarding technique (ultrasound use, multiple punctures) and year of training were associated with outcomes. Structured training reduces the rate of complications related to CVC insertion, especially regarding infections.