Background In low-income settings, cancer is often diagnosed in advanced stages due to late presentation. Good public awareness of cancer signs and symptoms has a positive impact on the time patients take before they present to healthcare professionals. Therefore, this study examined public knowledge and awareness of cancer signs and symptoms as well as risk factors in the Gaza Strip. Methods This was a cross-sectional study. Participants were recruited from adult visitors (≥18 years) to governmental hospitals covering all five governorates of the Gaza Strip, and adolescent students (15 to 17 years) from ten high schools in corresponding locations. Visitors to oncology departments were excluded. An Arabic version of the Cancer Awareness Measure (CAM) questionnaire was completed in a face-to-face interview. It described demographic data and knowledge of: cancer prevalence, age-related risk, signs and symptoms as well as risk factors both in recall and recognition questions. Results A total of 2886 participants (out of 3033; response rate= 95.2%) with a mean age of 24.9±11.9 years, completed the questionnaire, including 1457 (50.5%) adolescents (781 females; 53.6%) and 1429 (49.5%) adults (702 females; 49.1%). About two thirds (n= 1885) thought about cancer as unrelated to age. Only 196 participants (6.8%) identified colorectal cancer as the most common cancer among men. Awareness of cancer signs/symptoms was poor to fair, where ‘lump’ was most commonly recognized (n= 2227, 77.2%) and ‘change of bowel habit’ the least (n= 670, 23.2%). Only 217 participants (7.5%) had a good level of recognizing risk factors with ‘smoking’ being the most identified and ‘eating less than five portions of fruits and vegetables a day’ the least. Adults were persistently better at identifying most cancer signs/symptoms and risk factors than adolescents, except for recalling ‘unexplained pain’, ‘persistent cough/hoarseness’, ‘non-healing ulcer’, ‘smoking’, and ‘eating less than five portions of fruits and vegetables a day’. Conclusion Public awareness of cancer signs/symptoms and risk factors needs to improve in Gaza to facilitate early presentation and diagnosis. Combining the delivery of public campaigns with tailored education to population groups, including the youth, may increase their knowledge and maintain its impact and sustainability.