Age, gender, and performance status (PS) are important patient characteristics which might influence to cancer symptom profile. We conducted a secondary analysis of a symptom database to examine any interaction of these factors on symptom prevalence. 38 symptoms were assessed in 1000 consecutive patients with advanced cancer. The association of the three demographic factors with each symptom was examined using logistic regression analysis. Eight symptoms were associated with more than one of the three factors. Model-based estimates of symptom prevalence were calculated for 30 groups based on combinations of age, gender, and ECOG PS (0-4). Prevalence differences between various groups >10% were empirically classified as clinically relevant. The frequency of all eight symptoms (pain, constipation, sleep problems, nausea, anxiety, vomiting, sedation, and blackouts) was associated with more than one of the demographic characteristics of age, gender, and PS level. The prevalence of all eight decreased with older age. Females had more nausea, anxiety, and vomiting than males; males greater sleep problems. The prevalence of constipation, sedation, and blackouts was higher with worse PS, whereas pain and anxiety became less common with worse PS. Age, gender, and PS appeared to be associated with variations in the prevalence of eight gastrointestinal and neuropsychological symptoms in cancer patients. They should be included as important variables in clinical practice symptom research data.