Background: Abnormal Uterine Bleeding (AUB) is considered one of the most common and challenging problems presenting to the gynecologists and accounts for as many as one third of all outpatients. Material and Methods: A prospective study  comprising 440 cases of endometrial lesions in women of all age groups in Western Rajasthan presenting with  AUB  were studied with respect to age, clinical presentations, histopathological features and the definitive diagnosis of cause of AUB is done by reviewing and studying the histopathological slides. Results: The mean age of women presenting with AUB was 41 years and menorrhagia was the most common clinical presentation. The most common histopathological finding was normal physiological changes of menstrual cycle, seen as proliferative and secretory phase of endometrium in 70.50% cases, followed by benign lesions in 22.3% cases, malignant lesions in 5.5% cases and precursor lesions in 1.8% cases.  Most common lesion of endometrium was simple endometrial hyperplasia comprising 65 cases. Conclusion:  Abnormal uterine bleeding in perimenopausal women is most commonly dysfunctional in origin. There is an age specific association of endometrial lesions presenting with AUB. Diagnostic curettage or endometrial biopsy is mandatory without delay in all cases of perimenopausal and postmenopausal bleeding to rule out malignancy.