The temperature (T) dependent Electron spin resonance
(ESR) study was carried out on La0.7-xBixCa0.3MnO3 (x = 0, 0.035, 0.07, and 0.35) samples prepared by sol-gel method. The reduction in the paramagnetic to ferromagnetic (PM-FM) transition temperature (TC) was observed for x = 0.35 sample. ESR studies also reveal the phase separation (PS). The PM phase exists in a wide temperature region even below TC. The ESR
linewidth above TC and its temperature dependence is not affected by Bi doping.