We derived constraints on cosmological parameters using weak lensing peak statistics measured on the $sim130~{rm deg}^2$ of the Canada-France-Hawaii Telescope Stripe 82 Survey (CS82). This analysis demonstrates the feasibility of using peak statistics in cosmological studies. For our measurements, we considered peaks with signal-to-noise ratio in the range of $ u=[3,6]$. For a flat $Lambda$CDM model with only $(Omega_{rm m}, sigma_8)$ as free parameters, we constrained the parameters of the following relation $Sigma_8=sigma_8(Omega_{rm m}/0.27)^{alpha}$ to be: $Sigma_8=0.82 pm 0.03 $ and $alpha=0.43pm 0.02$. The $alpha$ value found is considerably smaller than the one measured in two-point and three-point cosmic shear correlation analyses, showing a significant complement of peak statistics to standard weak lensing cosmological studies. The derived constraints on $(Omega_{rm m}, sigma_8)$ are fully consistent with the ones from either WMAP9 or Planck. From the weak lensing peak abundances alone, we obtained marginalised mean values of $Omega_{rm m}=0.38^{+0.27}_{-0.24}$ and $sigma_8=0.81pm 0.26$. Finally, we also explored the potential of using weak lensing peak statistics to constrain the mass-concentration relation of dark matter halos simultaneously with cosmological parameters.
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