According to one embodiment, there is provided a memory system that is connected to a host apparatus. The memory system includes a transmitting port and a controller. The transmitting port transmits a transmission signal to the host apparatus. The controller includes a first output interface that is connected to the transmitting port and a second output interface that is connected to the transmitting port. The memory system is configured such that a drivability of an output from the first output interface is larger than a drivability of an output from the second output interface in a first mode.