Aim: To assess the performance of CarieScanPRO™ with radiovisiography (RVG) and international caries detection and assessment system II (ICDAS-II) to detect the occlusal carious lesions in the mandibular primary molars. Methods: Fifty healthy children of age 5–7 years were involved and evaluated for caries using visual ICDAS-II, RVG, and CarieScanPRO™. Operative intervention pit and fissure opening served as a gold standard for comparison of the three methods of examination. The sensitivity, specificity, accuracy, and area under the receiver operating characteristic (ROC) curve (Az) of the methods were calculated at enamel (D1), dentinoenamel junction (DEJ) (D2), and dentine (D3, D4). Results: At D1 threshold, CarieScanPRO™ showed higher values of sensitivity and accuracy (0.97 and 0.88) and RVG specificity (0.92). At D2 threshold, visual examination showed higher values of sensitivity (0.80) whereas CarieScanPRO™ showed specificity and accuracy of 0.98 and 0.87. At D3, D4 threshold, CarieScanPRO™ showed higher values of sensitivity, specificity, and accuracy (0.1, 0.98, and 0.99). Higher positive predictive value (PPV), negative predictive value (NPV) and lower false discovery rate (FDR), false-positive rate (FPR) were shown by CarieScanPRO™. The intraexaminer repeatability for CarieScanPRO™ was good with kappa at D1 (0.77) and D3, D4 (0.98). Conclusion: CarieScanPRO™ showed higher reproducibility compared to visual examination and RVG for the detection of enamel and dentinal caries. Higher accuracy of CarieScanPRO™ can be used for longitudinal monitoring of occlusal caries in primary teeth with low sensitivity at DEJ.