A dishwasher comprising: a sump configured to store wash water; a main arm disposed at the sump to have the wash water supplied from the sump flowed therethrough; at least one auxiliary arm (140, 150) rotatably disposed at the main arm to spray the wash water; and at least one auxiliary arm connection member disposed at the main arm to rotatably support the at least one auxiliary arm (140, 150), wherein: at least one auxiliary flow passage through which the wash water flows is formed in the at least one auxiliary arm (140, 150); at least one transfer flow passage communicating with the at least one auxiliary flow passage to supply the wash water is formed in the main arm; the at least one auxiliary arm connection member comprises a flow tube disposed at the main arm to communicate with the at least one transfer flow passage and the at least one auxiliary flow passage, characterized in that the at least one auxiliary arm connection member further comprises a shaft inserted into the at least one auxiliary flow passage, a protrusion protruding from the shaft, and at least one support rib (165a, b, c) configured to connect the flow tube to the shaft to support the shaft; and a departure prevention part configured to come in contact with the protrusion to prevent the departure of the at least one auxiliary arm (140, 150) is disposed at the at least one auxiliary arm (140, 150). a sump configured to store wash water; a main arm disposed at the sump to have the wash water supplied from the sump flowed therethrough; at least one auxiliary arm (140, 150) rotatably disposed at the main arm to spray the wash water; and at least one auxiliary arm connection member disposed at the main arm to rotatably support the at least one auxiliary arm (140, 150), wherein: at least one auxiliary flow passage through which the wash water flows is formed in the at least one auxiliary arm (140, 150); at least one transfer flow passage communicating with the at least one auxiliary flow passage to supply the wash water is formed in the main arm; the at least one auxiliary arm connection member comprises a flow tube disposed at the main arm to communicate with the at least one transfer flow passage and the at least one auxiliary flow passage, characterized in that the at least one auxiliary arm connection member further comprises a shaft inserted into the at least one auxiliary flow passage, a protrusion protruding from the shaft, and at least one support rib (165a, b, c) configured to connect the flow tube to the shaft to support the shaft; and a departure prevention part configured to come in contact with the protrusion to prevent the departure of the at least one auxiliary arm (140, 150) is disposed at the at least one auxiliary arm (140, 150). at least one auxiliary flow passage through which the wash water flows is formed in the at least one auxiliary arm (140, 150); at least one transfer flow passage communicating with the at least one auxiliary flow passage to supply the wash water is formed in the main arm; the at least one auxiliary arm connection member comprises a flow tube disposed at the main arm to communicate with the at least one transfer flow passage and the at least one auxiliary flow passage, characterized in that the at least one auxiliary arm connection member further comprises a shaft inserted into the at least one auxiliary flow passage, a protrusion protruding from the shaft, and at least one support rib (165a, b, c) configured to connect the flow tube to the shaft to support the shaft; and a departure prevention part configured to come in contact with the protrusion to prevent the departure of the at least one auxiliary arm (140, 150) is disposed at the at least one auxiliary arm (140, 150).