Problem: Crystalline lens has a mechanistic role in eyes with narrow angles, either independently or in combination of other ocular biometric parameter. We have tried to assess role of lens vault in patients of angle closure presenting to our glaucoma OPD. Approach: It was prospective hospital based cross sectional study. The lens vault measured on anterior segment optical coherence tomography in patients of primary angle closure with age 40-70 years and cataract grade 2 and 3 (LOCS) and compared to age and cataract matched controls. Results calculated using chi-square and student t test as required. Findings: Present study compared 100 cases of angle closure and 100 cases as controls from similar age and cataract grade matched normal population. Mean age of patients in angle closure group was 52.40 ± 6.73 years. Mean age of normal control population group was 51.48 ± 5.47 years.  The difference was statistically insignificant. Number of subjects of angle closure with grade 2 cataract were 38 and grade 3 cataract were 62. Cataract grading in normal control group were grade 2 in 46 cases and grade 3 in 54 cases. The difference was statistically insignificant.  The mean lens vault in patients of angle closure group was 898.14 ± 26.5 µm. The mean lens vault in patients of normal control group was320 ± 27.2 µm. The difference was highly significant. Conclusion: In the presence of visually significant cataract, consider lens extraction as the initial treatment option for the management of primary angle closure.