Abstract　  

    In a cold dark matter (CDM) universe, dark matter haloes form hierarchically through accretion and merging. When a small halo merges to a larger one, it becomes a subhalo of the larger system. Numerical simulations show that massive dark matter haloes are populated with numerous subhalos. It has long been known that subhalos are modified by the environmental effects due to host haloes, including tidal stripping and impulsive heating. We show that a promising way to investigate the satellite-subhalorelation is through a stacking analysis of galaxy-galaxy lensing with large surveys. Using CFHT-Stripe82 survey, we made the first measurement of subhalo galaxy-galaxy lensing signal.