Abstract: Electrocardiograms (ECG) of one hundred conventional FMMU albino guinea pigs under narcosis were analysed. The results were as follows ：①The main waves of QRS were always downstroke in all aVR leads and some aVL leads. However, the waves of P and T were upside - down. While in the other leads, the main waves of QRS were upstroke, and the waves of P and T appeared upright,②S — T segments were easier to be noticed,and ③ There was no significant difference in ECG parameters between FMMU albino guinea pigs and ordinary pigmented guinea pigs.