Introduction: Determining whether an ovarian tumor is benign or malignant before surgery can change the treatment plan and aid in early identification. Transvaginal ultrasonography, in particular, is a useful technique for ovarian tumor detection. Early diagnosis is crucial since the majority of ovarian cancers are epithelial ovarian cancers (EOC), which grow quickly. Treatment can be more successful if a gynecologic oncologist is consulted right away to diagnose the type of tumor. Methods: A descriptive cross-sectional study was conducted among 400 patients presenting with adnexal masses at the Saudi Hospital for Obstetrics and Gynecology in Khartoum, Sudan, from January to May 2025. Transvaginal and abdominal ultrasonography were utilized to evaluate adnexal lesions. Data on patient demographics, symptoms, and medical history were analyzed to assess correlations with ultrasound findings and final diagnoses. Results: The study found that the most affected age group by ovarian tumors was those in 26-40 years, which constituted 42% and 41-55 years represented 28.25%. Approximately 43.3% of patients were asymptomatic, more than half were symptomatic, with pain being the most prevalent symptom. Ultrasonography classified 68.8% of masses as benign and 22% as malignant. Significant associations were found between ultrasound features, such as irregular contour, ascites, papillary projections, and vascularity, and the presence of malignancy. Older age and a history of breast cancer were also significantly associated with malignant lesions. Statistical analyses demonstrated that specific ultrasonographic features effectively predict ovarian malignancy. Conclusion: Ultrasonography is an efficient and dependable method for identifying, assessing, and categorizing ovarian cancers. Combining the patient's age, medical history, and ultrasound characteristics improves diagnostic precision, enables prompt and effective treatment, and lowers the risk of surgery.