Objectives : Evaluating the adherence to HIV Pre-Exposure Prophylaxis (PrEP) is essential for increasing its utilization and decreasing the risk of HIV transmission among Davao City's vulnerable groups. Methods : The research method utilized in the study is a quantitative, retrospective, descriptive research design. This method was employed to retrospectively review the de-identified data, which involved the fill and refill dates of PrEP and tablets supplied, to calculate the Proportion of Days Covered (PDC) among individuals in Davao City from January 2021 to December 2023. The study also included some demographic characteristics such as age and gender. Results : From 178 data entries collected, the age group of 25 to 34 years old was found to have the highest HIV PrEP use (52.25%), followed by those between 18 to 24 (30.90%), 35 to 44 (13.48%), and 45 years old and older (3.37%). Out of 178, only 2 clients were female. Furthermore, 73.60% of the 178 entries in the pharmacy records were identified to be taking PrEP daily. Descriptive statistics showed that the frequency of adherent clients across the years were 36.36%, 44.74% and 38.46%, respectively. Furthermore, the average PDC through the years was found to be 70.13%, 80.48%, and 72.8%. Age did not significantly affect adherence to PrEP during the years investigated (p-values > 0.05). Conclusion : Adherence to PrEP improved consistently in 2022 but declined in 2023, showing erratic adherence rates. Furthermore, adherence to HIV PrEP in Davao City was found to be suboptimal and while there are clients who are adherent, many are not. The results emphasize the need for targeted interventions and suggest that other socio-behavioral factors may play a role in this. To improve adherence and prevent HIV contractions, both short-term actions like public education campaigns about HIV PrEP and long-term plans like incorporating PrEP into the community pharmacies can be contributive.