Memory expansion card of blade server

The utility model discloses a memory expansion card of a blade server, in particular to a module with a memory expansion interface in the blade server, comprising an SAS control chip and a memory unit. A memory expansion board is provided with an SAS backplane interface, and hard disks are connected with the memory expansion board by an SAS backplane. The memory expansion of a single computing blade can be realized by installing a hard disk interface on an IO expansion module connected by the computing blade, each hard disc can realize hot plug, the expansion mode of at most six hard disks is installed, and the memory capacity of the blade server is extended furthest.