The previous data interpretation equation for medium and low stress is no longer applicable when in-situ tests are carried out in deep soils. In this paper, the cone penetration test in silica sand with different relative density and confining pressure level was performed in a self–developed high–pressure calibration chamber, and the Arbitrary Lagrangian–Eulerian method, a large deformation finite element approach, was used to study cone penetration in silica sands. A modified Mohr–Coulomb constitutive model was introduced to describe the internal friction and dilatancy angle varied with the plastic shear strain in silica sands. A method for determining shear modulus by correcting the bending element tests is proposed. Numerical results of cone tip resistance agree reasonably well with calibration chamber tests. An empirical equation for cone tip resistance varied with different relative density was established under high stress condition.