  The large scale structure formation in the standard Einstein gravity at later
time is uniquely determined by the expansion history H(z) measured by the
geometrical factor. A possible departure from the expected standard structure
formation is detectable by growth structure test. We design new deviation
parameters to test standard gravity at large scales and estimate the expected
errors by weak lensing experiment. The effective Newtonian constant G_N at the
present time can be constrained around 10% accuracy by measuring the difference
curvature perturbations (\Phi-\Psi)/2 within 2% accuracy.
