Background: Chronic sinusitis is a common condition that can greatly affect patients' quality of life. It is essential to understand patients' knowledge, attitudes, and practices (KAP) regarding chronic sinusitis and its surgical treatment to enhance patient outcomes and optimize clinical management. This study aimed to investigate KAP among chronic sinusitis patients to identify areas for targeted intervention and improvement. Methods: A cross-sectional study was conducted with chronic sinusitis patients at the Ear, Nose, and Throat Department of Liaocheng People's Hospital from June 2019 to June 2022. Demographic data and KAP were collected using self-designed questionnaires. Results: A total of 567 valid questionnaires were included, yielding a validity rate of 99.3%. Among the respondents, 314 were male (55.38%), and 260 individuals (45.86%) lived in urban areas. The mean scores for KAP were 7.86 +/- 2.39 (possible range: 0-12), 17.69 +/- 1.94 (possible range: 8-40), and 7.86 +/- 2.39 (possible range: 7-35), respectively. Structural equation modeling demonstrated a direct impact of knowledge on attitude (beta = -0.500, p < 0.001) and practice (beta = 0.261, p = 0.001), and a direct impact of attitude on practice (beta = 1.737, p < 0.001). Conclusion: Patients with chronic sinusitis demonstrated insufficient knowledge and negative attitudes and practices towards both the condition and its surgical treatment. These findings highlight the need for targeted interventions to improve patient education and awareness. By addressing knowledge gaps and fostering positive attitudes towards treatment options, healthcare providers can empower patients to make informed decisions and enhance their management of chronic sinusitis.