<p class="0abstract"><span lang="EN-US">To cope with the security challenges brought by the popularization of wireless sensor network (WSN), a new random key pre-distribution scheme for WSNs based on the grid deployment theory of Blom mechanism is proposed. The core idea is to divide the network area where the nodes are into different types of hexagonal grids and nodes in different grids use different ways to create keys. Theoretical analysis and simulation results show that the scheme has better connectivity, local security and global security. In view of the existing storage consumption problems, a deterministic key establishment scheme is proposed based on the irregular network model. The simulation results show that the effective coding mechanism introduced optimizes the storage consumption in the network range. It also has a higher security threshold and absolute connectivity, and the enemy's ability to resist capture attacks is stronger.</span></p>