We consider N × N symmetric one-dimensional random band matrices with general distribution of the entries and band width $W$.   The localization - delocalization conjecture predicts that there is a phase transition on the behaviors of  eigenvectors and  eigenvalues of the band matrices. It occurs at $W=N^{1/2}$. For wider-band matrix, the eigenvalues satisfied the so called sine-kernal distribution, and the eigenvectors are delocalized. With Bourgade, Yau and Fan, we proved that it holds when $W\gg N^{3/4}$. The previous best work required $W=\Omega(N).$