The invention discloses a Fischer-Tropsch synthesis device for improving the feeding and startup efficiency of industrial Fischer-Tropsch synthesis, which comprises a catalyst feeding unit, a synthesis gas hydrogen and carbon separation unit, a catalyst reduction unit and a Fischer-Tropsch synthesis unit. The invention also discloses a corresponding method utilizing the same device. Operation is started after initial feeding and startup and an overhaul, a catalyst is reduced in a Fischer-Tropsch synthesis reactor, and the one-time reduction amount of the catalyst is large, so that the time forthe synthesis reactor to reach a full load is greatly shortened, the feeding and startup efficiency is improved, and the benefit is increased. In-situ reduction is carried out in the synthesis reactor, the reduction method is simple and easy to implement, the operation is simple and convenient, and the startup cost is saved. By adopting the process, the feeding and start-up time can be greatly shortened, and the operation efficiency of the device is improved.