Objective To analyze the noise monitoring results of key industry workplaces in Luoyang of Henan Province from 2021 to 2024, and to provide basis for formulating relevant prevention and control measures. Methods Noise monitoring was conducted using judgment sampling method in accordance with the Implementation Plan for Monitoring Occupational Hazard Factors in Workplaces in Luoyang City. The data were evaluated according to Occupational Exposure Limits for Hazardous Factors in Workplaces-Part 2: Physical Factors (GBZ 2.2-2007), and were analyzed using descriptive epidemiological methods. Results From 2021 to 2024, a total of 1 421 employers in key industries were monitored in Luoyang, with 435 exceeding the standard, and the employer exceeding rate was 30.61%. A total of 4 521 workplace sites were monitored, with 1 265 exceeding the standard, indicating a workplace exceeding rate of 27.98%. There were 4 383 noise-exposed positions were monitored, with 784 indicating the standard, and the position exceeding rate was 17.89%. From 2021 to 2024, the employer exceeding rates were 44.53%, 41.48%, 22.08%, and 20.88%, respectively. The workplace exceeding rates were 40.07%, 36.83%, 23.45%, and 18.85%, respectively. The position exceeding rates were 22.25%, 36.07%, 12.68%, and 8.99%, respectively. All showed a downward trend. There were differences in the exceeding rates among employers in different counties/districts, enterprise sizes, and industries. Among them, Song County, large enterprises, and the mining industry had higher employer exceeding rates, which were 56.96%, 38.18%, and 55.16%, respectively. Conclusion From 2021 to 2024, the noise monitoring over-standard rate in key industries in Luoyang showed a downward trend. However, noise hazards still exist. It is necessary to strengthen the supervision of key counties/districts, enterprises, and industries, promote the use of engineering control measures and protective equipment, and reduce both the exposure intensity and time of workers to noise. All sectors of society need to participate in protecting workers’ physical and mental health.