To examine the knowledge, behavior, and attitudes toward medical genetics among obstetrics and gynecology, pediatrics, and neurology residents and specialists, who encounter the highest number of patients with specific genetic disorders, in their everyday practice. The cross-sectional study involved 182 nongenetic residents and specialists in the Republic of Croatia, who completed a validated online questionnaire anonymously and voluntarily. The questionnaire consisted of five groups of questions: general information, knowledge, behavior in practice, attitude toward genetic testing, and additional education in medical genetics. The median score for overall knowledge of medical genetics was 70.2% among obstetrician-gynecologists, 80.5% among pediatricians, and 76.7% among neurologists (P < 0.001, lowest median in obstetrician- gynecologists). When asked about their behavior in daily practice, around 90% of respondents admitted the possibility of not recognizing patients with genetic disorders, which is why more than 90% emphasized the need for additional education in medical genetics. In addition, the respondents showed a positive attitude toward genetic testing, but they did not feel educated enough to interpret the results of genetic testing. The results highlight the need for further genetic education of non-genetic health professionals, which would lead to greater confidence and ability to recognize patients with genetic disorders, select the appropriate genetic testing method and achieve more efficient communication with patients.