NOVELTY - Conducting Fischer-Tropsch synthesis reaction comprises: (i) introducing gas raw materials containing carbon monoxide and hydrogen into a Fischer-Tropsch reactor, and incubating with a cobalt-based catalyst of Fischer-Tropsch synthesis reaction to generate hydrocarbon products, and gaseous byproducts; (ii) taking at least a portion of the tail gas containing gaseous byproducts and unreacted gas raw materials from step (i) and mixing them with fresh gas raw materials; and (iii) introducing the gas materials from step (ii) into the Fischer-Tropsch reactor and repeating steps (i) and (ii).    USE - The method is useful for conducting Fischer-Tropsch synthesis reaction to generate hydrocarbon products (claimed), preferably liquid hydrocarbon product.    ADVANTAGE - The method can effectively reduce water content generated in the reaction system by a recycling operation and a dewaterization unit and can prevent the cobalt-based catalyst from being affected by the moisture and from losing activity while obtaining a relatively higher spatial efficiency of the reactor and a relatively higher space-time yield rate.    DETAILED DESCRIPTION - Conducting Fischer-Tropsch synthesis reaction comprises: either (i) introducing gas raw materials containing carbon monoxide and hydrogen into a Fischer-Tropsch reactor and incubating the gas raw materials with a cobalt-based catalyst of Fischer-Tropsch synthesis reaction to let the carbon monoxide and hydrogen to react with each other under a controlled reaction condition to generate hydrocarbon products containing two or more carbon atoms and gaseous byproducts containing water, methane and carbon dioxide, where the controlled reaction condition reduces the single-cycle conversion rate of carbon monoxide, (ii) taking at least a portion of the tail gas containing gaseous byproducts and unreacted gas raw materials from step (i) and mixing them with fresh gas raw materials containing carbon monoxide and hydrogen, removing carbon dioxide and water from the mixed materials, and (iii) introducing the gas materials from step (ii) into the Fischer-Tropsch reactor and repeating steps (i) and (ii); or the step (i) as above per se, (iia) taking at least a portion of the tail gas containing gaseous byproducts and unreacted gas raw materials from step (i) and putting them under a condition of conversion to let methane to oxidize in the presence of water, (iiia) taking the resulting gaseous products from step (ii) and mixing them with fresh gas raw materials containing carbon monoxide and hydrogen, removing carbon dioxide and water from the mixed materials, and (iva) introducing the gaseous materials from step (iii) into the Fischer-Tropsch reactor and repeating steps (i), (ii) and/or (iii).