Background: Adherence to local standard guidelines is seen as a pragmatic way to measure and improve the quality of future prescribing in ambulatory care to reduce morbidity, mortality and healthcare costs. Objectives: To evaluate adherence to the Ghana Standard Treatment Guidelines (STGs) for the empirical antibiotic treatment of ambulatory care patients with community-acquired pneumonia (CAP) in a region in Ghana and factors associated with it. Methods: A cross-sectional survey was conducted using a checklist to collect data from the hospital electronic database, which included sociodemographic details, payment type and clinical information of all ambulatory patients attending Keta Municipal Hospital, diagnosed and managed for CAP from September 2018 to January 2019. Prescriptions were assessed for adherence to the Ghana STG based on choice of antibiotics. A χ2 test and multiple logistic regression were subsequently conducted. Results: A total of 1929 patient records with diagnosis of CAP within the study period at the ambulatory clinic were identified. The overall rate of adherence to the Ghana STG was 32.50% (n = 627). From the patient records collected, 62.50% were female, 41.84% were children (0-12 years), and 97.15% had a valid national health insurance status. Adherence was associated with the duration of antibiotic prescribing, number of additional antibiotics prescribed and some patients' clinical characteristics. Conclusions: The rate of adherence to Ghana STG among the study population was low. Efforts must be made to train and encourage prescribers to follow empirical guidelines to reduce inappropriate selection of antibiotics in the ambulatory care settings.