Most pregnancy-related complications and undesirable outcomes are preventable by effective interventions at a reasonable cost. These interventions are mainly deployed during the antenatal phase and are included under the umbrella of Antenatal Care (ANC). This study aimed to measure and quantify the adequacy of ANC provided by the Ministry of Health (MoH) facilities in Jeddah and to find potential factors influencing ANC. In this cross-sectional study design, we used Adequacy of Perinatal Care Utilization (APNCU) index to measure the adequacy of ANC. Data was collected from September 2023 to March 2024 in two randomly selected Ministry of Health (MoH) hospitals interviewing mothers as well as collecting data from medical records. A total of 303 mothers participated in this study. Mothers’ mean age was 31 years old, and 50% of them received higher school education. Prevalence of adequate ANC was 64.7% while 35% received inadequate ANC. There was a significant association between adequacy of ANC and mothers’ level of education, time taken to reach nearest primary care center, number of total pregnancy, and total number prenatal visits. This is the first study to shed light on the prevalence of adequacy of ANC in Saudi Arabia and factors associated with it, and would pave a way to investigate adequacy of ANC on a national level that will aid policymakers in developing and implementing effective antenatal care preventive measures, hence helping in improving women’s health and their babies as well. .