Purpose: The purpose of this study was to determine factors associated with observed levels of adherence to ant rabies PEP vaccine among animal bite victims in Machakos level five hospital. Methodology: The study used Cross sectional study design. It utilized both qualitative and quantitative methods. Data was collected by use of semi-structured questionnaires, physical examination sheet and key informant interview. The study population was victims of animal bites who revisited the health facility for the scheduled PEP vaccine. Random Sampling was used to select the revisiting animal bite victims until a sample size of 68 was achieved. Purposive sampling was used to select health care workers directly involved in management of animal bite victims until a sample size of three was achieved. Quantitative data was analyzed using SPSS version 20 and excel computer programs. Qualitative data was analyzed by content analysis. Binary logistic regression and multivariate regression was done. Results: The study findings established that knowledge of rabies significantly affects the level of adherence to antirabies PEP vaccine. At least 48.50% of the respondents admitted that they have no knowledge of rabies and 75% had no knowledge of prevention of rabies. The study also found out that affordability of the cost of PEP vaccine is statistically associated with adherence to anti-rabies PEP vaccination. Unique contribution to theory, practice and policy: The study concluded that: the level of adherence and the overall awareness not only of anti-rabies PEP vaccine, the follow-up of victims to check on the completion of the anti-rabies PEP vaccine schedule but also the management of wounds before visiting health facilities among animal bite victims in MKS L5 Hospital is low, thus a major public health concern both to the community and the county government.