This paper introduces the current status of an orbital debris evolutionary model for low Earth orbit, named LEODEEM and being developed under collaboration of Japan Aerospace Exploration Agency. The objective of low Earth orbit modeling is to discuss on effective mitigation measures to conserve orbital environment since study and long term prediction of orbital debris environment are urgent needs for secure human space development and exploration. In this model, an object with a perigee altitude less than 2,000 km is considered as a low Earth orbit object. The model calculates long-term evolution of artificial objects greater than 1 cm in low Earth orbit with future space operations, including collisions and explosions. The details of the model and results will be presented in this paper.