Abstract: An environmentally secure polished rod liner head is provided for use on a polished rod employed in an oil well pumping system for vertically reciprocating a string of sucker rods, the polished rod extends through a stuffing box, the polished rod liner head having a body with a passageway therethrough receiving the polished rod, a polished rod liner removably secured to the lower end of the body and encompassing the polished rod, bolts extending laterally through the upper end of the body to secure the body to a polished rod so that the polished rod liner is reciprocated with the polished rod and a closure member within the body passageway above the polished rod liner biased to close in the event the polished rod should be unexpectedly removed from the body to thereby prevent hydrocarbons from being discharged through the polished rod liner and into the atmosphere.