Objective:To establish human induced pluripotent stem cell derived atrial and ventricular cardiomyocytes for cardiotoxicity assessment. Method:Temporarily manipulating retinoic acid signal to differentiate atrial and ventricular cardiomyocytes. Flow cytometry analysis and immunofluorescent staining were conducted to detect the cardiac-specific marker:α-actinin and ventricle-specific marker:MLC2v. qRT-PCR was done to detect ventricle-specific marker(MLC2v,MYH7)and atrial-specific marker(NR2F2,KCNA5). Cell viability and calcium transient were assessed to evaluate cytotoxicity and cellular electrophysiological alterations caused by different drugs(terfenadine,sotalol and ibutilide). Result:The results of flow cytometry,immunofluorescent staining and qRT-PCR demonstrated that ventricle-specific markers were highly expressed in RAi group while atrial-specific markers were expressed in RA group. By assessing calcium transient and cell viability,we proposed a drug assessment platform using hiPSC-ACM and hiPSC-VCM. After treated with terfenadine,cytotoxic effects occured at a concentration of 100 μmol/L both in hiPSC-ACM and hiPSC-VCM. Meanwhile,both sotalol and ibutilide exhibited cardiotoxicity potential at a concentration of 1 mmol/L. In the following calcium transient assessment,the amplitudes of calcium transient were significantly decreased in hiPSC-ACM after 1 μmol/L sotalol and 1 μmol/L ibutilide treatment,while in hiPSC-VCM,the amplitude showed no significant difference in such concentrations. The amplitudes of calcium transient were significantly decreased in both groups when the concentration of terfenadine reached to 1 mmol/L. Conclusion:By modulating retinoic acid signaling during hiPSC differentiation,we generated atrial and ventricular cardiomyocytes. Human induced pluripotent stem cell-derived atrial and ventricular cardiomyocytes were useful models for assessing cardiotoxicity of drugs by detecting calcium transient.