Chronic progressive ophthalmoplegia(CPEO) is a vague clinical entity, which needs further understanding and there is still intense controversy about the classification on the Syndrome of Progressive External Ophthalmoplegia. In our country two cases of similar disease were reported with the title of oculocraniosomatic disease and CPEO with ragged red fiber. Authors experienced a 39 year-old woman with typical Kearns-Sayre syndrome(KSS) and a 44 year-old man with ophthalmoplegia plus syndrome. The case with Kearns-Sayre syndrome had an invariable triad of 1) chronic progressive external ophthalmoplegia and onset before 20 years of age, 2) retinal pigmentary degeneration of salt & pepper pattern and 3)mitochondrial abnormalities with additional findings of increased cerebrospinal fluid protein and cerebellar ataxia rhe other case with ophthalmoplegia plus with ragged red fiber syndrome had similar symptomatology to Kearns-Sayre syndrome except for typical retinal pigmentary degeneration. Both cases showed electromyographic myopathic findings and typical histopathologic features as ragged red fiber and paracrystalline mitochondrial aggregations. Therefore authors would say that these clinical different phenotypes of mitochondrial abnormality should be understood in detail by the biochemical investigations.