Gestational Diabetes Mellitus (GDM) is a glucose intolerance disorder first detected during pregnancy and may lead to various complications for both the mother and the fetus. The low level of knowledge among pregnant women regarding risk factors, prevention, and management of GDM can increase the risk of pregnancy complications. Health education is one of the important strategies to improve pregnant women’s understanding of GDM. This study aimed to analyze the effect of educational interventions on the prevention and management of gestational diabetes on the knowledge level of pregnant women in the working area of Puskesmas Pante Raya in 2026. This study used a quantitative method with a pre-experimental one group pre-test and post-test design. The research sample consisted of 60 pregnant women selected using a purposive sampling technique. Data were collected using pre-test and post-test questionnaires and analyzed using the Wilcoxon Signed Rank Test. The results showed that before receiving education, most respondents had moderate and low levels of knowledge. After the educational intervention, there was a significant improvement in the knowledge level of pregnant women. The average knowledge score increased from 62.5 in the pre-test to 85.3 in the post-test, with an increase of 22.8 points. The Wilcoxon test results showed a p-value of 0.000 (p < 0.05), indicating a significant effect of educational interventions on the prevention and management of gestational diabetes on the knowledge improvement of pregnant women. The study proved that educational interventions are effective in increasing pregnant women’s knowledge regarding the prevention and management of gestational diabetes, and therefore can be used as a promotive and preventive strategy in antenatal care services at public health centers.