Purpose: In Cambodia, noncommunicable diseases (NCDs) account for 64% of all deaths. A lack of risk perception of NCDs leads to poor measures of their prevention and management. This study aimed to investigate Cambodians’ risk perceptions of NCDs based on the health belief model. Methods: A cross-sectional design was used, and using convenience sampling, participants included 200 Cambodians aged 40 years or older. A face-to-face administered structured questionnaire was used to assess demographic characteristics, health behaviors, and risk perceptions of NCDs. Results: Of the constructs of NCD risk perception, perceived severity (88.2%) and benefits (86.3%) were high, but relative to these, perceived cues to action (64.1%), barriers (63.5%), and self-efficacy (58.1%) were low. Conclusion It is important to improve perceived self-efficacy in government health promotion, outreach, and improvement programs and to reduce perceived barriers through medical tests either by facility-based delivery or via outreach health services in Cambodia.