AIM: To analyze ocular biometric parameters among candidates for cataract surgery.METHODS: This cross-sectional study was conducted on 4 607 cataract patients(4 607 eyes)in Farabi Eye Hospital, Tehran, Iran from January 2017 to September 2021. Axial length(AL), keratometry(Kf, Ks and Km), and anterior chamber depth(ACD)were assessed using IOLMaster 700. All eyes were categorized into three groups based on AL: short eyes(22 mm25 mm)and ACD as follows: low(3.00 mm3.60 mm).RESULTS: The mean age of patients was 60.3±14.1(range 8-95)years [2 243(48.69%)female and 2 364(51.31%)male]. The AL, ACD and mean keratometry ranges were 23.1 to 23.4 mm, 3.1 to 3.2 mm and 44.50 to 45.00 diopter(D), respectively. The mean amount of ACD in the long eyes group was significantly higher than the normal and short eyes group(P<0.001). The mean AL in the high ACD group was significantly higher than low and normal ACD patients(P<0.001). But the mean of Kf, Ks and Km in the low ACD and long eyes group was significantly higher than in high ACD and short AL groups(P<0.001).CONCLUSION: Those candidates with long eyes had deeper ACD with flatter cornea; while short eyes had shallower ACD with steeper cornea. Also, patients with high ACD had longer AL with flatter cornea, and patients with low ACD had lower AL with steeper cornea.