Introduction Cancer patients’ quality of life (QoL) significantly influences treatment response and mortality rates. Understanding QoL domains among patients with cancer and what affects it can help create interventions that improve QoL and ease patients’ experience. This study measures the OoL among patients with cancer and influencing factors. Methods A prospective cross-sectional questionnaire-based study included cancer patients aged >18 currently receiving treatment. The questionnaire collected social and economic data, followed by the validated Arabic version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30). Means and standard deviations for described numeric variables and frequencies and percentages described categorical variables. Analysis of variance, F-tests, and P-values were reported. Results Among 182 cancer patients, 60% were female. Younger patients exhibited higher QoL in physical and role functioning ( P = .016 and .03) and experienced more significant financial impact ( P = .0144). Females reported more adverse effects from cancer symptoms, including fatigue, nausea, vomiting, and pain (36.7% vs 25.5%, P = .005; 20.6% vs 11.5%, P = .0186; 34.7% vs 25.1%, P = .0281). Single patients had superior QoL in physical functioning compared to others ( P = .0127). Patients traveling long distances were more likely to face adverse financial consequences ( P = .007). Asthmatic patients exhibited lower QoL in physical, role, and cognitive functioning (72.3 vs 37.8, P = .0147; 76.4 vs 22.2, P = .0024; 84.7 vs 44.4, P = .0038) and reported increased dyspnea and appetite loss (16 vs 55.6 and 26.1 vs 66.7, both P < .05). Conclusion Factors influencing QoL in Saudi cancer patients include age, marital status, gender, hospital distance, and chronic conditions. Thus emphasizing the necessity for personalized care strategies to enhance outcomes and alleviate the overall burden of cancer care.