Objective: To analyze the diagnostic value of transvaginal color Doppler three-dimensional ultrasound combined with transabdominal color Doppler ultrasound for ectopic pregnancy. Methods: The clinical data of 83 patients initially diagnosed with suspected ectopic pregnancy in our hospital from March 2021 to March 2025 were retrospectively collected. All patients underwent comprehensive diagnoses including medical history screening, symptom screening, laboratory tests, and ultrasound examinations. The results of transvaginal three-dimensional ultrasound examination and color Doppler ultrasound examination of the patients were respectively statistically analyzed. Taking the comprehensive diagnostic results as the "gold standard", the diagnostic value of the two ultrasound examinations alone and in combination for ectopic pregnancy was analyzed. Results The comprehensive diagnostic results showed that among the 83 patients suspected of having ectopic pregnancy, 60 cases were clearly diagnosed as ectopic pregnancy, accounting for 72.29%. Taking the comprehensive diagnostic results as the "gold standard", the consistency Kappa of the "gold standard" results of transvaginal three-dimensional ultrasound examination, transabdominal color Doppler ultrasound examination alone and combined examination for diagnosing ectopic pregnancy was 0.682, 0.521 and 0.848 respectively, and the consistency of the combined diagnosis was better than that of the "gold standard" results. Moreover, the accuracy and sensitivity of the combined diagnosis were both higher than those of the individual diagnoses of the two (P < 0.05). Conclusion: The diagnostic results of transvaginal three-dimensional ultrasound combined with transabdominal color Doppler ultrasound for ectopic pregnancy are highly consistent with comprehensive diagnosis. Compared with the application of the two alone, it can improve the accuracy and sensitivity of diagnosis.