Abstract: The paper reports that mitochondrial permeability transition (MPT) may exist in Honglian cytoplasmic male sterile (HL-CMS) rice.The results also showed that there are significant differences of MPT occurrence and characteristics among the sterile line,YuetaiA (YTA),maintainer line,YuetaiB (YTB),and the hybrid,Honglian Number 2 (HL2) derived from the cross of YTA×9311.The MPT of YTA is more sensitive than those of YTB and HL2 to changes of pH and ion density.Although HL2 has the same origin of CMS as that of YTA,and difference from the normal cytoplasm of YTB,the occurrence and characteristics of permeability transition pore (PTP) and MPT of HL2 are obvious different from YTA and much more similar to that of YTB.It is suggested that MPT might be involved in the abortive process of HL-CMS.