The neural mechanism underlying the acquisition of scripts of a second language (L2) is an open issue. The aim of the present study is to investigate the neural specialization for L2 scripts by focusing on the influence of overall visual similarity between first language (L1) and L2. EEG signals were recorded in native Chinese Han readers at the first and ninth months of learning Korean as L2 when they passively viewed Chinese characters (CC), high Chinese-like Korean characters (HKC) and low Chinese-like Korean characters (LKC). Time-frequency analysis revealed that event-related synchronization in the theta band (θ-ERS) is sensitive to CC and Korean character (KC), with a stronger and more left-lateralized θ-ERS for CC and a clear initial response trend of left-/right-lateralization for HKC/LKC. After nine months of learning, increased θ-ERS was shown for both HKC and LKC, whereas robust left lateralization was observed only for HKC. These results suggest that high visual similarity to native language scripts may facilitate the progress of neural specialization for L2. These findings were discussed in light of the “neural recycling” theory.