Background: In resource-constrained settings, primary health centers (PHCs) are critical for universal health coverage. Laboratory service is one of its important components. While PHC and its performance are focused, its laboratory service has been neglected in developing countries. A routine checkup is a general physical evaluation and is not performed for a specific injury, illness or condition. A routine checkup in laboratory service is one of its important components are beneficial for detecting diseases in early stages when treatments are most effective. In the Kingdom of Saudi Arabia (KSA), free-of-charge healthcare services including the analysis to be carried out in laboratories are offered to citizens. However, studies are consistently finding that Saudi people are not taking advantage of the free routine checkups. Two survey studies one involving a nationally representative sample of Saudi adults and the other involving Saudi students studying in the Saudi or out of Saudi found that three-quarters of the participants had never had a routine checkup. A third study reported that 65.7% of Saudis had never had a routine checkup in laboratory. Aim of the study: To assess Assessment of Factors Influencing the Utilization of laboratory services on Public Primary Health Care Services in Makah Al-Mokarramah City, Saudi Arabia in 2022. Methods: A cross-sectional study was conducted on laboratory services on Public Primary Health Care center in Makah Al-mokarramah 2022 Saudi Arabia. The study employed a self-administered questionnaire to collect data from patients attending both public PHC centres (or outpatient clinics) in Makkah city. The questionnaire was designed to collect data on a number of variables related both to health services users and providers. Descriptive statistics socio-demographic and medical data were used to determine the significant variables which may influence the utilization of this service. Results: most of the participants (35.0%) were in the age group 50-60 years the majority of them were males (66.0%) also majority of participant are Saudi were(82.0%) majority of participant married were (67.0%), also the patient's with satisfaction and heave a significant relation between the satisfaction and frequency while P-value <0.001 and X2 35.363, Conclusion Focus on laboratory services is needed to enhance the existing PHCs performance. Skill-up gradation of existing could help in improving the contribution of the existing laboratories in PHC functioning.