The present invention provides a computer subsystem and a computer system. The computer subsystem includes L composite nodes, each composite node includes M basic nodes, each basic node includes N central processing units CPUs and one node controller NC, where any two CPUs in each basic node are interconnected, each CPU in each basic node is connected to the NC in the basic node, the NC in each basic node has a routing function, any two NCs in the M basic nodes are interconnected, and a connection between the L composite nodes formed through a connection between NCs enable communication between any two NCs to require at most three hops. The computer subsystem and the computer system according to embodiments of the present invention can reduce the kinds and the number of interconnection chips, and simplify an interconnection structure of a system, thereby improving reliability of the system.