PURPOSE: To shorten a reduction period by bringing a Fischer-Tropsch catalyst into contact with a hydrogen-contg. gas at a specified pressure, increasing the pressure rapidly to a specified pressure and activating the catalyst by contact with the hydrogen-contg. gas.

CONSTITUTION: In a process for activation of a Fischer-Tropsch catalyst, the catalyst is brought into contact with a hydrogen-contg. gas in a first stage at a pressure of up to 5 bar, the pressure is rapidly increased to at least 10 bar, and the catalyst is brought into contact with a hydrogen-contg. gas in a second stage at this pressure. Wherein, the first stage is operated at the pressure up to 3 bar and the second stage is operated at the pressure of at least 20 bar, preferably at least 25 bar. Further, a hydrogen content in the hydrogen contg. gas is increased from 1 vol.% to 100 wt.% and the catalyst is brought into contact with substantially pure hydrogen in the second stage. Thereby, the catalyst having improved selectivity for 5C+ products and improved stability is obtained.