Wierer finished with a time of 21:26.5, 5.9 seconds ahead of Ingrid Landmark Tandrevold who equalled per personal best with silver after shooting perfectly throughout and goes into second in the overall standings.
It's a repeat of last season when she won her maiden sprint race.
'Look at the time!' - Weirer takes Sprint victory in Austria
Hanna Oeberg came in fifth with Marte Olsbu Roesieland in seventh.
The result means that Wierer strengthens her grip on the yellow bib with the pursuit to come on Sunday in Austria.
“[It was] strange you know because after the prone shooting I was sure that the race was over,” Wierer said afterwards.
Wierer: I thought the race was over after prone shooting!
“Because I felt really strange and I didn’t know if it was good or bad. Finally I was just concentrating on my standing shooting and it worked really well.”
The defending champion is already setting the early pace and her rivals face a battle to wrest the leader’s bib from her grasp.
“I love the fact that she’s not complicated about her biathlon, she just says ‘today I went out there and I just did what I’m trained to do,'" Mike Dixon said on commentary.
Highlights: Wierer wins second Sprint in a row
“She’s kind of carefree and that’s a lovely place to be to not get stressed out about being the best. Shje could well take that yellow bib all the way to the end of the season.”
Dixon also raised that it’s not since the 2011/12 season when someone has won the opening two sprints of the women’s season, Magdalena Forsberg was the athlete in question that time.
Meanwhile in the men’s sprint Johannes Thingnes Boe won his second event of the year ahead of Simon Desthieux and Alexandr Loginov.
Boe won the opening Sprint in Sweden but he had to surrender the yellow bib after rival Martin Fourcade led home a French one-two-three in the Individual.
However Boe responded well early on as he shot perfectly in the prone section.
Highlights: Boe goes back to top of standings with Sprint victory
Although he missed one whilst standing Boe’s skiing was more than good enough to give him a large margin of victory, with a time of 25:07.8.
His lead looked to be over twenty seconds at one stage until Desthieux put in a blistering final lap and finished 7.8 off the World Cup champion.
As for Fourcade after a perfect opening to his shooting a couple of misses put him in a difficult situation and he wasn’t able to make up the time, having to settle for tenth in the end.
Boe now goes back to the top of the World Cup standings on 151 points, Desthieux is second on 135, just four ahead of third-placed Fourcade.