To efficiently obtain an alkanol for synthetic intermediates, etc., of chemicals by feeding an alkane into a reactor containing an alkane- assimilating bacterium or its enzyme and a culture medium and fermenting the resultant alkanol while keeping it in a specific concentration.

In a method for producing an alkanol by feeding an alkane into a reactor containing an alkane-assimilating bacterium [e.g. Methylosinus trichosporium]OB3b(ATCC35070)] or an enzyme which an alkane-assimilating bacterium can produce (e.g. methanemonooxygenase) and a culture medium and recovering an alkanol from the reactor, the alkane is reacted with the bacterium while keeping an alkanol concentration in the reactor in an amount of ≤10 mM based on bacterial cell unit weight to selectively provide the objective alkanol useful as a synthetic intermediate, etc., for various chemicals.