  Dark matter direct detection experiments mostly operate at deep underground
laboratories. It is necessary to consider shielding effect of the Earth,
especially for dark matter particles interacting with a large cross section. We
analyzed and simulated the Earth shielding effect for dark matter at the China
Jinping Underground Laboratory (CJPL) with a simulation package, CJPL Earth
Shielding Simulation code (CJPL\_ESS), which is applicable to other underground
locations. The further constraints on the $\chi$-N cross section exclusion
regions are derived based on the studies with CDEX experiment data.
