The purpose of this research is to analyze the topic of “Assessment of Sound Level Inside the Mosques in Seeb City (Muscat), Oman”. The mosque plays a significant role in the cultural and religious landscape of Oman. This study examines the sound levels in selected mosques in Oman to determine whether they are compliant with local sound regulations. There are 10 mosques from Seeb city (Al-Hail) were selected as a sample frame of this research study. Since the recitation is performed aloud, Maghrib and Isha's prayers were taken for this study. A sound level meter was placed inside each mosque to measure the inner sound. The questionnaire is used for the data collection. The SPSS software is used for doing the data analysis. The study revealed that that the sound level during Maghrib and Isha prayer at most mosques not exceeds the NIOSH recommended level of 85 decibels (8 hours). However, prayers don't continue for eight hours. Mosques differ in acoustical conditions and other factors, which results in different sound levels. A study of ten selected mosques showed that the average sound level (LAeq) Maghrib prayer is 79 ± 4.7 dB-A dB-A while Isha prayer is 79 ± 5 dB-A. Among the mosques, mosque M8 has the highest sound level (LAeq), indicating that it is close to the usual limits recommended by NIOSH. A relatively more serene environment could be found at mosques M3 during the Maghrib and Isha prayers. It is recommended that to ensure a conducive auditory environment in mosques, sound levels must be monitored and managed to ensure both spiritual engagement and good hearing health. Also, acoustic treatment like soundproof panels should be implemented to improve sound quality and reduce sound levels inside the mosque based on the opinions of respondents (worshipers).