In Japan, the heavy workload managed by cardiologists might make it difficult for female cardiologists to work comfortably, and some hospital managers hesitate to employ female cardiologists. Are the clinical outcomes of patients with cardiovascular diseases affected by the cardiologist's gender? In our previous study, the risk of emergency readmission within 30 days after discharge was found to be significantly lower for patients treated by female cardiologists than for those treated by male cardiologists. Compared to male counterparts, female cardiologists were more likely to practice evidence-based and guideline-directed medicine and communicate with other experts, that is, they are better at solving complex problems in the attending doctors' team. In addition, female cardiologists probably maintain more robust physician-patient communication and successfully provide more fine-tuned and patient-centered preventive care than male cardiologists. In Japan, the rate of female doctors 21.1% is the lowest among the rates for the Organization for Economic Co-operation and Development countries. Under such a situation, in our hospital, a representative teaching hospital where female cardiologists constitute larger than other hospitals in Japan, better clinical outcome was observed in the patients treated by female cardiologists over those treated by male cardiologists. Considering the preference of medical management by female cardiologists, an increase in the number of female cardiovascular medicine practitioners is necessary from the perspective of patients' clinical outcomes.