Objective To detect the value of three-dimensional (3D) ultrasound diagnosis in common ocular fundus diseases. Methods Two-dimensional (2D) images of 38 patients with common ocular fundus diseases were three-dimensionally reconstructed via 3D ultrasound workstation. The 3D images reflecting the ocular diseases were analyzed. Result In 38 patients with common ocular fundus diseases, there was vitreous hemorrhage in 16 patients, retinal detachment in 12, choroidal detachment in 5, and intraocular space occupying lesion in 5. Compared with the 2D images, 3D reconstructed images reflect the lesions more intuitionistically, displayed the relationship between the lesions and the peripheral tissues more clearly, and revealed the blood flow more specifically. During a scanning examination, 3D reconstructed technology provided the diagnostic information of section of X, Y and Z axises simultaneously which shortened the time of examination; the condition of any point of lesions and the relation between the lesion and the peripheral tissues could be gotten by the tools like cut and chop provided by 3D imaging software itself, which avoided detecting the same lesion with different angles and lays and proved the diagnostic efficacy. Conclusions 3D ultrasound diagnosis is better than 2D in diagnosis of vitreous, retina, choroid, and intraocular space occupying lesion. 3D ultrasound diagnosis is a complementarity for the 2D one, and the Z axis changes the former observational angles which may provide the new way of precise diagnosis. (Chin J Ocul Fundus Dis, 2005, 21: 381-383)