BACKGROUND: Automated assays have recently been developed for efficient serological testing of syphilis infection. Here, we evaluate the performance of new automated serological assays for syphilis infection. METHODS: The precision, linearity, and detection limit of the automated kits AutoLab rapid plasma reagin (RPR) (IVD-RPR) and AutoLab (Treponema pallidum Latex Agglutination) TPLA (IVD-TPLA) (IVDLab Co., Korea) were evaluated using an immunoturbidimetric method. In addition, the results of these tests were compared with those obtained using the HiSens Auto RPR LTIA (HBi-RPR) and HiSens Auto TP LTIA (HBi-TPLA) tests (HBi Co., Korea) with 122 serum samples. RESULTS: Both the IVD-RPR and IVD-TPLA kits showed acceptable precision for the positive controls (IVDLab Co., Korea). The within-run and total precision of IVD-RPR were better than those of HBi-RPR at cut-off levels (CV, 7.0% to 7.4% for IVD-RPR; CV, 33.3% to 40.0% for HBi-RPR). The IVD-RPR and IVD-TPLA kits demonstrated acceptable linearity and limits of detection. The agreement rate between IVD-RPR and HBi-RPR was 83.60% (102/122). Nineteen samples were IVD-RPR negative but HBi-RPR positive; 12 of these were from patients with a history of syphilis. The agreement rate between IVD-TPLA and HBi-TPLA was 96.72% (118/122). All discrepant results were IVD-TPLA positive and HBi-TPLA negative. CONCLUSIONS: IVD-RPR and IVD-TPLA exhibited acceptable precision, linearity, and limits of detection for the diagnosis of syphilis infection. IVD-RPR was suitable for monitoring syphilis infections with good precision that was near cut-off levels. IVD-TPLA was useful for detecting primary syphilis infection.