The utility model relates to a distributor and a plate-fin heat exchanger provided with the same. The distributor is characterized by comprising a distributor shell which is provided with an upper opening and a lower opening, the bottom of the distributor shell is a rectangular framework, a plurality of separation boards are vertically installed inside the distributor shell at intervals in an inserted mode, and the separation boards divide the rectangular framework into a plurality of gas-phase channels. The distributor further comprises a liquid-phase channel which is a rectangular pipe, the liquid-phase channel is transversely installed and penetrates through all the separation boards, positions of the distributor shell, corresponding to two ends of the liquid-phase channel, are respectively provided with a liquid-phase inlet, and a liquid-phase inlet end socket is installed on the outside of each liquid-phase inlet. A baffle partition is installed in the middle of the liquid-phase channel, a part of the top of the liquid-phase channel, between each two separation boards, is provided with a liquid outlet hole, and a gas-liquid mixing channel is formed between each two separation boards and above each liquid outlet hole. The distributor and the plate-fin heat exchanger provided with the distributor can meet requirements of uniform distribution of gas and liquid inside the heat exchanger and normal working in the rocking condition at sea, and can be widely used in float production storage and offloading (FPSO) of liquefied natural gas in the rocking environment at sea.