Objectives To explore the inter‐ and intra‐observer reliability of Sonography‐based Volume Computer Aided Diagnosis (SonoVCAD) in the display of 8 diagnostic planes of fetal echocardiography and to evaluate its efficiency. Methods Three‐dimensional volume data sets of the 56 normal singleton fetuses were acquired from a 4‐chamber view by using a volume probe. After processing the data sets by using SonoVCAD, 8 cardiac diagnostic planes were displayed automatically. Three doctors with different experiences of performing fetal echocardiography evaluated each diagnostic plane and the success rates of 8 diagnostic planes were calculated. Inter‐observer and intra‐observer reliabilities were estimated by Cohen's kappa statistics. Results A total of 276 volume data sets acquired from the 56 normal fetuses were used for SonoVCAD analysis and display. The success rate of each diagnostic section was more than 90%, ranging from 90.6% to 99.6%. Among 276 volumes, 81.5% (225/276) of volumes were able to generate all 8 diagnostic views successfully. Moderate to substantial agreement (kappa, 0.509–0.794) was found between 2 less experienced operators. Moderate to near‐perfect agreement (kappa, 0.439–0.933) was found between an expert and 2 less experienced sonographers. Intra‐observer reliability was substantial to near‐perfect (kappa, 0.602–0.903). The efficiency of SonoVCAD was assessed. The expert spent less time than 2 less experienced examiners (P < 0.001) but no significant difference was found between 2 less experienced examiners (P = 0.176). Besides, SonoVCAD consumed significantly less time than 2‐dimensional ultrasound (P < 0.001). Conclusions SonoVCAD can significantly improve the success rates of 8 diagnostic planes in fetal echocardiography with low operator dependency, good reproducibility and high efficiency.