Introduction: The aim of the study was to evaluate the cytotoxicity, radiopacity, pH, flow and solubility of a silicone-based and an epoxy resin-based endodontic sealer: GuttaFlow 2 and AH Plus, respectively. Methods: Cytotoxicity, radiopacity and flow evaluation were performed following ISO requirements. pH was measured at periods of 3, 24, 72, 168 h. Cytotoxicity was evaluated by MTT assay to check the Balb/c 3T3 cells viability at 1 to 3 week periods. Data were statistically analysed by ANOVA and Tukey test with a significance level of 5%. Results: GuttaFlow 2 was non-cytotoxic in all tested periods. AH Plus was more cytotoxic than GuttaFlow 2 when freshly mixed and after 1 week (P 0.05). After 2 weeks, AH Plus becomes noncytotoxic. Although AH Plus presented higher radiopacity than GuttaFlow 2 (P 0.05), both sealers showed minimum required values. GuttaFlow 2 and AH Plus presented a pH level close to neutral in all tested times. AH Plus also showed significantly lower flow than that of GuttaFlow 2 (P 0.05). Both sealers showed values complying with the solubility minimum requirements. Conclusion: GuttaFlow 2 demonstrated suitable biological and physicochemical properties for an endodontic sealer. Schlagwörter: AH Plus, cytotoxicity, GuttaFlow 2, physicochemical properties, root canal sealer