Background: Occupational stress can lead to poor health and work-related injuries. Nurses have a unique work place environment that can impact job-related stress in a unique way. Objectives: To determine the prevalence and associated factors of job stress among nurses in primary health centers in Arar city. Methods: This cross-sectional study was carried out on 101 nurses covering all primary healthcare centers (n=12) in Arar city, Saudi Arabia between December 2017 and February 2018. All nurses working in primary healthcare levels, of all ages, sexes, Saudi and non-Saudi were eligible for study inclusion. Nurses with mental health problems and those of work duration less than one year were excluded from the study. Data were collected using a self-administered questionnaire including demographic characteristics of nurses and a work stressor questionnaire to evaluate job stress among them. The data were entered and analyzed using IBM© SPSS© Statistics version 20. Chi-Square test of independence and Fisher Exact test were used. p≤0.05 was considered significant. Results: All nurses at primary healthcare centers in Arar city were included in the study (101nurses). The most frequent areas of work-related stress among nurses were time pressure (42.6%), followed by boredom-induced stress (32.7%), pressure on the job (31.7%), work underload stress (26.7%), and disagreement and indecision (25.7). Almost one-third (34.7%) of the nurses had work-related stress. Higher educated nurses (Bachelor or above) were more likely to have work-related stress compared to diploma educated nurses; 55.2% versus 26.4% (OR=3.4, CI: 1.3-8.4, p=0.006) Conclusion: Work-related stress is a considerably prevalent problem among nurses working at primary healthcare centers in Arar city, Saudi Arabia as it impacts almost one third of them. Application of interventional programs to relieve sources of stress, and providing more training of nurses on stress management is a necessity.