Apparatus and methodology for lawn mower security systems provide the ability to safeguard ride-on style lawn mowers against unauthorized cranking of its engine if the mowers have push/pull mower deck or power-takeoff (PTO) switch technology. Security components secured to a PTO or mower deck switch to prevent the ability to position such switch in a disengaged position. Therefore, existing safety and interlock features of the existing ride-on mower otherwise prevent someone from being able to crank the mower, which helps to guard against unauthorized use and/or theft of the equipment.