The invention provides a two cycle engine which effectively suppresses an intrusion of a combustion gas into a crank chamber. Further, the invention provides a two cycle engine tool provided with the two cycle engine mentioned above. An engine is provided with a cylinder having two scavenge air ports at different positions in a cylinder circumference direction, and scavenge air inflow ports communicating individually with these two scavenge air ports via a scavenge air passage, and a piston in which two scavenge air communication ports are formed at positions corresponding to the scavenge airinflow ports, and is structured to swirl the gas flowing into the piston from the cylinder through the scavenge air passage, in an upper portion of the internal space of the piston, and retains the gas in the upper portion of the internal space of the piston.