OBJECTIVE: To evaluate influences of regular-dose of adriamycin (ADR) on heart function and sarcoplasmic reticulum (SR) Ca2+ -ATPase in cardiomyocyte of rabbits. METHODS: Nine rabbits received intraveneous injection of ADR (2mg/kg) once a week for 8 weeks, the rabbits injected with saline were used as control group. Cardiac output (CO), blood pressure (BP), mean artery pressure (MAP), left ventricular systolic pressure( LVSP), left ventricular end-diastolic pressure (LVEDP), calcium in cardiomyocyte (MyoCa2+) of rabbits and SR Ca2+ -ATPase activity were examinated 3 weeks after the final injection. RESULTS: CO, LVSP and SR Ca2+ -ATPase activity were significantly decreased in ADR treated group compared with the control group. Conversely, LVEDP and MyoCa2+ were significantly increased in ADR treated rabbits. CONCLUSION: Heart function can be decreased by regular-dose of ADR in injection. Calcium overload in cardiomyocyte and decrease of SR Ca2+ -ATPase activity is important physiopathologic mechanism in ADR-induced impairment of heart.