Ultrasound biomicroscopy (UBM) is a high-frequency B-mode ultrasound that provides high-resolution images of the anterior segment. This technique is a helpful imaging method in the diagnosis of anterior segment diseases such as pigmentary glaucoma, plateau iris, and malignant glaucoma, as well as intraocular tumors. Ultrasound biomicroscopy is particularly useful in evaluating lesions behind the iris, examining masses located in the ciliary body, differentiating cystic and solid lesions, and assessing intraocular spread. This method is also important in planning treatment for anterior segment tumors, evaluating treatment outcomes and complications. It plays a significant role in the differential diagnosis of anterior segment diseases such as pigmentary glaucoma, plateau iris, and malignant glaucoma.