The Reactor Experiment for Neutrino Oscillation (RENO) has been taking electron antineutrino ($overline{ u}_{e}$) data from the reactors in Yonggwang, Korea, using two identical detectors since August 2011. Using roughly 500 live days of data through January 2013 we observe 290,775 (31,514) reactor $overline{ u}_{e}$ candidate events with 2.8 (4.9)% background in the near (far) detector. The observed visible positron spectra from the reactor $overline{ u}_{e}$ events in both detectors show discrepancy around 5 MeV with regard to the prediction from the current reactor $overline{ u}_{e}$ model. Based on a far-to-near ratio measurement using the spectral and rate information we have obtained $sin^2 2 theta_{13} = 0.082 pm 0.009({rm stat.}) pm 0.006({rm syst.})$ and $|Delta m_{ee}^2| =[2.62_{-0.23}^{+0.21}({rm stat.})_{-0.13}^{+0.12}({rm syst.})]times 10^{-3}$eV$^2$.
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