Background: Abnormal Uterine Bleeding (AUB) is a very common complain that drives large number of patients to seek medical advice. Histopathological analysis of endometrial biopsy is the basic mean to diagnose the major causes of AUB. The aim of this study is to analyze a range of histopathological finding in endometrial biopsy obtained from patients presented with AUB to identify most common pathological changes in these biopsies in relation to age. Materials and Methods: A retrospective study of total number of 230 endometrial biopsy was done. The specimens were collected from a private histopathology laboratory in Benghazi during the period from January 2018 to December 2019. The histopathological patterns of endometrial lesions were observed in the different age groups and their frequencies and percentages were computed and analyzed. Results: These studies included patients with age range from 20 to 79 years. The predominant age group with AUB was perimenopausal age group (41-50years). The most common histopathological finding in this study was normal menstrual pattern (27%) followed by simple endometrial hyperplasia (16.5%) and endometrial polyp (16.5%). Other patterns identified were disordered proliferative endometrium (15.2%), irregular hormone response (4%), exogenous hormone changes (2.2%), Arias Stella reaction (3%), inactive endometrium (5.2%), and endometrial carcinoma (7%), and the majority was in >50 years. Conclusions: Histopathological examination of endometrial biopsy obtained by dilation and curettage showed a very large spectrum of endometrial lesions. by classifying these lesions based on age group a large panoramic view was obtained which will help in identify patients with high risk of precancerous lesion.