We report five cases of complex microphthalmia with other ocular malformations in infants or children, which were evaluated to investigate the relationship between the corneal diameters and total axial length. The size of the globe was measured by using computerized tomographic scans (CT scan), A-scan ultrasonography, or magnetic resonance imaging (MRI). There is a limited range of well-described malformation, including anterior or posterior segment dysgenesis or combined pathology such as corneal opacity, small cornea, iris hypoplasia, lens dislocation, cataract, chorioretinal coloboma, persistent hyperplastic primary vitreous (PHPV), retinal dysplasia, and intraocular tumor. Corneal diameters were correlated significantly with total axial length (r² = 0.88) and decreased linearly as the total axial length decreased in these cases. However, there was no relationship seen between the total axial length and posterior segment length (r² = -0.06). The results of this study may aid the clinical ophthalmologist to accurately understand or assess microphthamia combined with other ocular malformations.