Aim: The current study was conducted to investigate the efficacy of low-level laser therapy (LLLT) versus erythromycin phonophoresis in treatment of chronic rhinosinusitis. Design: Randomized controlled trial. Patients and Methods: The present work was conducted on sixty patients with chronic rhinosinusitis who participated in this study, their ages ranged from 30 to 60 years. The participants were selected from El-Monira general hospital, and randomly divided into two groups; each group consisted of 30 patients.