Chronic rhinosinusitis (CRS) is one of the most commonly reported chronic diseases. Refractory CRS represents a subgroup of patients who continue to be symptomatic even after adequate medical and surgical therapy. These patients started to form a significant portion of patients with CRS. Food elimination as a therapeutic method to control symptoms of different chronic diseases, such as eosinophilic esophagitis, asthma, and atopic dermatitis, has been described in the literature with variable success rates. To evaluate the effectiveness of food elimination therapy as adjuvant treatment in refractory patients having CRS with positive food sensitization. Prospective open-label study. Tertiary academic center. Consecutive adult patients with refractory nonobstructive CRS (patients who had persistent sinonasal symptoms despite endoscopic sinus surgery and patent sinuses ostia with adequate medical treatment) with positive food sensitization were included. Subjects were asked to eliminate the sensitized food from their diet. Clinical outcome was assessed using the Lund-Kennedy symptom and Lund-Kennedy endoscopic appearance scores. Twenty-two patients were initially enrolled in the study. Six patients were excluded; 4 were lost to follow-up, and 2 did not eliminate the causal food for the required period. The average age of the patients was 36 years old. There were 10 female and 6 male patients. Nasal discharge and facial pressure were the most common presenting symptoms. Shellfish, egg, and meat mix were the most common eliminated foods. There was a significant difference in the patients' Lund-Kennedy symptom and Lund-Kennedy endoscopic appearance scores at 6 and 12 weeks after food elimination therapy. Food elimination in refractory CRS is an effective adjuvant treatment and should be considered in the treatment algorithm of patients with persistent symptoms after successfully performed sinus surgery.