The knowledge spiral is a dynamic process for knowledge creation and evolution. It makes use of external connection to circulate, integrate, and accumulate all kinds of knowledge resources. The simmelian ties is an effective way to form the external connection. This study constructs the theoretical framework of transmission mechanism of simmelian ties on knowledge spiral. The theoretical framework uses high performance work practice system and knowledge fermenting as conduction and dual media channel variables. It takes high-tech manufacturing enterprises as empirical analysis objects. The study carries out empirical research on the transmission mechanism and media paths of simmelian ties on knowledge spiral by combinations of differential evolution algorithm method, extended DEMATEL method, and Bayesian estimation-SEM method. All of the above methodologies were approved by all human participants. Empirical analysis results indicates that strong and weak simmelian ties have significantly positive effects on high performance work practice system respectively; high performance work practice system significantly promotes knowledge fermenting while knowledge fermenting further plays significantly positive roles in promoting the knowledge spiral. This study takes high performance work practice system and knowledge fermenting as the breakthrough points. It then extends the transmission paths of simmelian ties on knowledge spiral from the perspectives of theoretical and empirical standpoints, which provides theoretical references and practical guidances for promoting and catalyzing knowledge fermenting and knowledge spiral for high-tech manufacturing enterprises.