Commenting on his upcoming award, Theroux said: "I came into the industry more than thirty years ago, feeling like a trespasser, an imposter, in a role meant for someone else, worrying that I would be found out, hoping I could keep going for a few more months, since I was enjoying it so much.
His big break came on Michael Moore's TV Nation series, as a roving reporter delving into offbeat culture, later striking up a deal with the BBC resulting in Louis Theroux's Weird Weekends.
NFTS chair Sophie Turner Laing praised Theroux's "immense contribution" to the world of factual filmmaking, adding: "His ability to connect with audiences and uncover powerful human stories makes him a true icon in the industry.".
NFTS graduates have gone on to win 15 Oscars and 166 BAFTAs since the school opened half a century ago, with current graduates' work on show at the BFI Southbank from Monday 3 March to Thursday 6 March.
Louis Theroux will be honoured with the prestigious National Film and Television School (NFTS) fellowship next month.