Background and objective Work-related musculoskeletal diseases (WMSDs) are one of the most common occupational health concerns among teachers. They refer to a variety of degenerative and inflammatory disorders that can be triggered by the work environment of the people affected. Teachers' health is substantially significant as it impacts their productivity at work. The aim of this study was to determine the prevalence, patterns, implications, and risk factors of WMSDs among teachers in the Eastern Province of Saudi Arabia. Methods This study involved a survey based on a cross-sectional questionnaire that was distributed to 404 random school teachers located in the Eastern province of Saudi Arabia. Information such as sociodemographic characteristics, workplace characteristics, characteristics of WMSDs experienced, associated factors, and impact of the symptoms experienced was collected. Questions related to symptoms were obtained from the Nordic Musculoskeletal Questionnaire and Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ). The collected data were then analyzed using the SPSS Statistics version 23.0 (IBM Corp., Armonk, NY). Results Among the participants, back pain, shoulder pain, and knee pain were the most reported symptoms of WMSDs in the past 12 months, while elbow pain was the least experienced; 41.1% had pain, discomfort, or numbness that prevented them from performing regular daily activities. The regression analysis revealed a relationship between moderate to severe pain and a pain duration of more than 12 months (p=0.001). Additionally, those who were able to perform lighter work and were not having depression had a low probability of pain persistence and were able to carry out their usual work while experiencing pain (p=0.002). Conclusions In the Eastern province of Saudi Arabia, WMSDs were commonly reported by school teachers. The prevalence of WMSDs among teachers was 41.1%. The pain was described as disabling and causing a negative impact on performance. The most common locations of symptoms were the back, shoulder, and knees. Risk factors for severe pain were female gender, sleeping for six to seven hours, and pain located in the neck shoulder, elbow, hand, thigh/hips, back, knees, and ankles. Furthermore, severe pain was associated with pain duration of more than 12 months, affecting sleep, causing anxiety, and mild depression. The impact of severe pain seriously affected the daily activities of teachers.