Background: Down syndrome (DS) is a chromosomal disorder that results in intellectual disability and growth problems. The worldwide incidence of this syndrome is 1 in 1000 births and increases exponentially with the maternal age. People with DS usually have reduced life expectancy and suffer from mental retardation, heart problems, Alzheimer's disease among other complications. However, the severity of the disease differs from patient to patient. Perceptions of the disease and the public attitudes towards people with Down syndrome are very important in the inclusion of these people in the community and the supporting families. Objectives: to assess the level of awareness, attitude and practice toward Down syndrome in Jeddah city to identify barriers. Methods: a cross-sectional analytical questionnaire-based study among the general population of Jeddah city. Results: a total of 360 subjects answered the questionnaires. The mean age was 36 years, it ranged from 16 to 70, with 45.2% females and 43.7% male respondents. Of these, 67% had attended college, 5% had a postgraduate degree, 23.5% had completed high school, and 3.1% had basic school. The majority of participants had a high level of monthly income (38%).  The majority of subjects included in the research were (59.6%) married and (51.3%) were unemployed. Most subjects (338) had poor knowledge about Down syndrome and there was no association between the knowledge and demographics of participants except for education at the higher levels of education, the more significant association with good knowledge. Conclusion: The results of the present study reveal that the knowledge about the Down syndrome was poor among the studied population. Also, education significantly impacts the knowledge of Down syndrome, thus there is a need for providing the population and patients with the necessary information to improve their Down syndrome awareness.