  The existence of primordial magnetic fields can induce matter perturbations
with additional power at small scales as compared to the usual $\Lambda$CDM
model. We study its implication within the context of two-point shear
correlation function from gravitational lensing. We show that primordial
magnetic field can leave its imprints on the shear correlation function at
angular scales $\lesssim \hbox{a few arcmin}$. The results are compared with
CFHTLS data, which yields some of the strongest known constraints on the
parameters (strength and spectral index) of the primordial magnetic field. We
also discuss the possibility of detecting sub-nano Gauss fields using future
missions such as SNAP.
