Purpose: Capseal I and Capseal II are calcium silicate and calcium phosphate based experimental root canal sealers. This study sought to evaluate the biocompatibility and mineralization potential of Capseal I and Capseal II. Materials and Methods: The biocompatibility and mineralization related gene expression (alkaline phosphatase [ALP], bone sialoprotein [BSP], and osteocalcin) of Capseal I and Capseal II were compared using methylthiazol tetrazolium assay and reverse transcription-polymerization chain reaction analysis, respectively. The results were analyzed by Kruskal-Wallis test. A P-value of <0.05 was considered significant. Result: Both Capseal I and Capseal II were favorable in terms of biocompatibility, influencing the messenger RNA expression of ALP and BSP. Conclusion: Within the limitation of this study, Capseal is biocompatible, with mineralization promoting potential; thus, it could be a promising root canal sealer.