This　paper　presents　an　accurate　heart　resistance　measurement　circuit　using　switched-capacitor　technique　for　cardiac　pacemaker.　A　reference　current　flows　through　the　heart,　resulting　in　a　voltage　drop　that　represents　the　heart　resistance.　And　then　the　voltage　drop　is　exactly　stored　and　amplified　by　the　switched-capacitor　amplifier　(SC-AMP)　while　the　voltage　error　is　considered　and　calibrated.　Compared　with　the　conventional　approach,　the　proposed　circuit　required　a　smaller　reference　current　flowing　through　the　heart　and　a　lower　precision　ADC　digitizing　the　voltage　drop.　Safety　can　be　guaranteed　due　to　smaller　reference　current　while　a　low　precision　ADC　relaxes　the　design　complexity　and　saves　power.　The　circuit　is　designed　in　0.35　mu　m　CMOS　process.　The　proposed　circuit　can　measure　heart　resistance　with　10　Omega　resolution.　The　average　power　consumption　is　about　3uA　under　2.8V　supply　during　the　12ms　resistance　measurement　period.　The　simulation　results　show　a　good　linear　relation　between　amplified　voltages　and　heart　resistances　in　the　range　of　500-4000　Omega.