Introduction: Sleep quality has become a public health concern due to serious impacts on individual’s health outcomes. Thus, this cross-sectional study aimed to determine the sleep quality and its associated factors among adults living in the province of Terengganu, Malaysia. Materials and Methods: Socio-demographic information was self-reported whilst anthropometric measurements were measured by trained researchers. Sleep quality was assessed using the validated Pittsburgh Sleep Quality Index (PSQI) whilst eating behavior was measured using the Dutch Eating Behavior Questionnaire (DEBQ). Descriptive statistics and multivariable linear regression models were employed using IBM SPSS version 25.0. Results: A total of 580 participants were enrolled (mean age = 29.1 ± 10.0 years; 51.2% female), of which 74.7% (n = 433) had poor sleep quality (PSQI global score > 5) with a total sleep duration per night of 6.2 ± 1.6 hours. Gender (p-value=0.044), educational level (p-value=0.001), emotional level (p-value=0.005) and external eating (p-value=0.026) were significantly associated with poorer sleep quality. Conclusion: This study underscored the high prevalence of poor sleep quality among adults living in Terengganu, Malaysia. The findings could serve as a basis for developing sleep education strategies that are tailored to improve sleep quality among adults.