A memory system includes: a memory device suitable for storing data; a controller suitable for controlling the memory device; an interface suitable for communication between a host and the controller; a register suitable for storing a parameter value set associated with a waveform and a magnitude of a signal provided by the interface to the host, wherein the controller is suitable for: performing signal transmission operations for candidates of the parameter value set, storing a new parameter value set, which is determined based on the responses of the signal transmission operations, in the register, and controlling the interface to transfer a new signal having adjusted waveform and magnitude to the host based on the new parameter value set.