Urogenital malignancies, encompassing urinary bladder cancer, prostate cancer, and renal cell carcinoma, pose significant diagnostic challenges due to overlapping histopathological features. GATA binding protein 3 (GATA3), a transcription factor associated with urothelial tissue, has shown promise as a potential diagnostic marker.This study aimed to investigate the incidence of these malignancies, explore GATA3's involvement in urothelial cancer (UC), and determine its role in distinguishing urogenital malignancies. A cross-sectional, retro-prospective, hospital-based study was conducted from May 2019 to April 2021. The surgical samples of patients who underwent transurethral resection of bladder tumour (TURBT), transurethral resection of the prostate (TURP), radical cystoprostatectomy, total and partial radical nephrectomy specimens during the study period were reviewed. Patients diagnosed with urinary bladder neoplasm and high-grade prostate neoplasm along with chromophobe, oncocytic, sarcomatoid variant and clear cell carcinoma, renalcell carcinoma were included. Immunohistochemical analysis of GATA3 expression was performed, with scoring based on nuclear staining intensity and percentage of tumor cells labeled. The study included 64 patients, predominantly males over 60 years. Personal habits revealed a high prevalence of smoking (85.9%). The most prevalent symptom was hematuria (75.0%), followed by hematuria with urgency (20.3%). The most common site of lesion was posterolateral (31.3%). Urothelial cancer was the most common malignancy, primarily high-grade. Strong positive GATA3 expression was significantly associated with high-grade UC (p=0.01) and invasion (p=0.01). However, low-grade UC and papillary urothelial neoplasm of low malignant potential exhibited moderate GATA3 expression. GATA3 demonstrated potential for distinguishing UC from other histological types. GATA3 expression correlates with high-grade urothelial cancer and invasive behavior, suggesting its utility as a diagnostic marker in challenging cases.