Dar-Zarrouk criteria were used to explore a study region in southwestern Nigeria that was covered by a crystalline groundwater basement complex to illustrate the possibility for groundwater protection. This was accomplished by determining if the research area's protective potentials were predominantly low, weak, moderate, or good. The study's protective potential was calculated using physical subsoil layer data such as apparent resistivity and layer thickness values. For vertical electrical probes, the Schlumberger electrode array arrangement was employed, and twenty probe locations were defined depending on the spread allowed and subsurface depth. The Dar-Zarrouk parameters revealed that there was 70% evidence of poor/weak groundwater protection potential within the study area, implying that the availability of profitable groundwater quality within the study area is envisaging a tragic development due to contaminating activities that could percolate from the topsoil to the subsoil in the near future. As a result, frequent assessment of adequate water quality development and standards is recommended within the environment for the safe use of groundwater resources.