An inbred maize line, designated PH3PR, the seeds and plants of inbred maize line PH3PR, methods for producing a maize plant, either inbred or hybrid, produced by crossing the inbred maize line PH3PR with another maize plant, and seed and plants produced therefrom. The invention also relates to methods for producing a modified PH3PR maize plant that comprises in its genetic material one or more transgenes or backcross conversion genes and to the transgenic and backcross conversion maize plants produced by these methods. This invention also relates to methods for producing other inbred and hybrid maize lines derived from inbred maize line PH3PR and to the inbred and hybrid maize lines so produced.