In the opening event of the 2021 champs in Pokljuka, Slovenia, Austria took silver, with Sweden in bronze.
Norway started the 2021 biathlon world championships with a gold medal in the mixed relay on Wednesday (10th February).
The event saw two men and two women for each team competing in four separate 7.5km legs at the track in Pokljuka, Slovenia
It's the third consecutive win in this event at the worlds for the Scandinavians, following their victories in Oestersund in 2019 and in Antholz-Anterselva in 2020.
"I have amazing teammates that made it easy for me. So I'm happy that I didn't ruin everything today. I'm really glad: I think that one of the reasons why we succeeded last year, was that we started with a gold so I really wanted the same start this year," Norway's final leg racer Marte Olsbu Roeiseland told IBU TV.
Roeiseland clinched her 10th world gold medal, joining Elena Golovina in second place in the all-time list for most world titles among women.
Fielding the world number 1 and 2 in both men's and women's rankings, the Norwegians were the pre-race favourites and controlled the event after building a comfortable lead through their star Johannes Thingnes Boe during the second leg.
Racing took place under snowy conditions with temperatures hovering around 0°C.
At the first exchange after three laps, Belarus was the surprise leader with Anton Smolski, followed by France with Emilien Jacquelin and Norway with Sturla Holm Laegreid, just a few seconds back.
Then men's world number one Boe took the lead for Norway, finishing 39 seconds ahead of France's Quentin Fillon Maillet. Ukraine and Canada followed around 55 seconds behind the leaders.
In the women's section, Tiril Eckhoff made only a few misses at the shooting range and Norway held the lead at the final exchange, with Yuliia Dzhima from Ukraine 39 seconds back in second, while Sweden and Austria battled for the third place, a further 18 seconds behind. France dropped to fifth, after a shaky shooting performance by a tired Anais Chevalier-Bouchet.
Despite three mistakes at the final shooting range, women's IBU World Cup leader Marte Olsbu Roeiseland completed the job for Norway as she crossed the finish line with a total time of 1:20:19.
Austria finished in second, 27 seconds back, with Sweden holding off Ukraine in third place. France finished in fifth, with last year's silver medallists Italy in sixth.
The 2021 biathlon world championships will continue on Friday, 12 February, with the men's 10km sprint event.