Abstract: Self-encoded spread spectrum(SESS) system employs random spreading sequences extracted from the information date to assure dynamically random varying. Performance analysis of self-encoded spread spectrum in additive white Gaussian noise channels is presented. An equivalent spread spectrum gain is used to describe the characteristic of self-encoded direct sequence spread spectrum system. Improved approaches generating self-encoded spread spectrum sequences are introduced. Theoretical analysis and computer simulation show that the spread spectrum gain of self-encoded direct sequence spread spectum system is almost the same to conventional spread spectrum system, but private of self-encoded direct sequence spread spectum system increases with variability of spread spectrum codes.