Background: Many published epidemiologic studies confirm a marked increase in the prevalence of asthma and allergic rhinitis (AR). Information is scarce regarding prevalence of AR and its association with asthma symptoms in Sudanese adults. Objective: To determine the prevalence of AR symptoms in the adults in Sudan and its relation with asthma symptoms and to identify the common trigger factors for allergy symptoms. Materials and Methods: A cross-sectional study was performed in Western, Northern, Eastern, and Central Sudan. An epidemiological questionnaire was distributed among the university students, academic staff, employees, and workers chosen randomly. The questionnaire included cardinal asthma symptoms and nasal symptoms in the past year when the subject did not have cold or "flu", their seasonal occurrence, trigger factors, and the family history of asthma and AR. Result: A total of 3,974 respondents in the age group of 18-67 years were included. Average prevalence of asthma symptoms in Sudanese adults was 10%. Prevalence of AR symptoms was 49% in the total sample with a significantly (p = 0.004) higher prevalence among patients with asthma (72.3%, n = 458) compared with patients without asthma (32.6%, n = 3516). There was a strong association between AR and asthma symptoms in all the sites (odds ratio: 2.91-4.52). Positive family history was a strong risk factor for AR in all the sites (odds ratio: 3.38-4.24). Symptoms of AR were more prevalent in winter season followed by summer and autumn. Home dust was found to be the most prevalent trigger factor for symptoms of AR in all the sites. Conclusion: There is a high prevalence of AR symptoms in Sudanese adults, which is significantly associated with asthma symptoms.