Johaug surpassed Winter Olympics legend and fellow Norwegian Marit Bjoergen’s tally with her 63rd victory, winning the 10km classic.
The 31-year-old, making her 200th World Cup start, managed to see off the challenge of Sweden's Ebba Andersson who finished 3.4 seconds behind with Finland's Krista Parmakoski taking third spot.
"It was a very good race today and I am really happy to stand at the top of the podium," said Johaug on her historic win.
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"It was a tough race but the people came down and cheered for us so I am really happy."
The home fans then roared Iivo Niskanen to victory in the 15km classic as he became the fourth man to win at least four individual World Cup distances events in Finland.
The Finnish star beat Russia's Alexander Bolshunov by 10.1 seconds while Norway's Hans Christer Holund came third.
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