Objective: Untreated protracted bacterial bronchitis (PBB), a chronic wet cough prevalent in children, may lead to chronic suppurative lung disease or bronchiectasis. However, clinical diagnostic criteria for PBB are nonspecific; thus, PBB may be misdiagnosed. Thus, we assessed the diagnostic value of fiberoptic bronchoscopy (FOB) and risk factors associated with PBB. Methods: Children with chronic cough at First Affiliated Hospital of Anhui Medical University from January 2015 to May 2020 were enrolled and allocated to a suspected PBB (n=141) or a non-PBB (n=206) group. All children underwent extensive laboratory, chest imaging, and allergen tests. Children with suspected PBB underwent FOB with bronchoalveolar lavage; lavage and sputum samples were cultured. Results: All 347 children had chronic wet cough for approximately 2 months. Of 141 children with suspected PBB, 140 received FOB with bronchoalveolar lavage. Visible tracheal changes included pale mucosa, mucosal congestion, edema, swelling, and increased secretions attached to the wall. Sputum was visible primarily in the left main bronchus (78.7%), left lower lobe (59.6%), right upper lobe (62.4%), and right lower lobe (64.5%). Sputum properties and amounts significantly differed between children with vs. without PBB ( P < 0.05). Dermatophagoides (odds ratio [OR], 2.642; 95% CI, 1.283–5.369) and milk protein (OR, 2.452; 95% CI, 1.243–4.836) allergies and eczema (OR, 1.763; 95% CI, 1.011–3.075) were risk factors significantly associated with PBB. Conclusion: Dermatophagoides, milk protein, and eczema were associated with increased risk of PBB. Sputum distribution and tracheal wall changes observed through FOB may distinguish PBB and assist in its diagnosis.