Background: Research is crucial for the scientific progress of the health of individuals, communities, and systems. The aim of this study was to assess the knowledge, attitude, motives and barriers among dentists and dental students in the western region of Saudi Arabia. Objective: This study aims to assess the level of knowledge, attitude, motives and barriers toward scientific research among dentists and dental students in the western region of Saudi Arabia. Methods: We conducted a cross-sectional study of 467 dentists and dental students using a convenience sampling method from seven dental colleges, major governmental and private dental clinics in the Western region of Saudi Arabia. We used a validated self-report questionnaire to collect data and assess the knowledge of, attitude towards and barriers to scientific research. Results: The participants (who are dentists and dental students) have a total knowledge score of m=4.57, SD=2.46, which is slightly lower than the midpoint. Participants who work in governmental clinic were significantly (F (2,464) =13.71, p<0.001) more knowledgeable than those who worked in private clinic and the students. Most participants had positive general and personal attitudes toward scientific research. Of the participants, 40.5% to 60.4% were involved in research activities, and 37.3% have submitted or published scientific articles. The most common motive for scientific research was receiving credit for post-graduate application (58.46%). The most common organizational barrier to conduct a research was the difficulty of finding research supervisor (39.19%) and lack of time due to work overload (32.55%). While most common personal barriers were lack of knowledge/skills (38.76%), lack of personal time (36.83%) and receiving credit for postgraduate application. Conclusion: Saudi dentists and dental students had a moderate level of knowledge and practice in research, but their attitude was highly positive. More efforts are needed to facilitate scientific dental research including supervisors’ availability and time allocation for research. The study has some limitations including using convenience sample from one region and self-report questionnaire that decreases the external validity of the study and increases the potential for self-reported biases.