Wiebes crossed the finish line ahead of Italy's Barbara Guarischi and Belgium's Marthe Truyen to take the overall race lead.
The top Polish finisher, Olga Wankiewicz, placed fifth in the 138.4 km stage from Tomaszów Lubelski to Zamość, a picturesque Renaissance town and a UNESCO World Heritage site about 60 km from the Ukrainian border.
Meanwhile, countrywoman Marta Lach was involved in a crash near the finish line, while Italian world champion Elisa Balsamo sustained minor injuries in the incident, Polish state news agency PAP reported.
The crash disrupted what had been expected to be a full bunch sprint.
Now in its fourth year, the three-stage women's Tour de Pologne is being held entirely in Poland's southeastern Lubelskie province on mostly flat terrain.
Stage two on Saturday covers 117.8 km between the towns of Włodawa and Lubartów.
This year's race features its strongest field to date, led by Wiebes and former world champion Lotte Kopecky.
A total of 110 riders from 20 teams are competing, including 14 Polish cyclists.
The women's Tour de Pologne is being held in Poland's picturesque southeastern Lubelskie province. Photo: PAP/Wojtek Jargiło
The 27-year-old Wiebes, who claimed the 128th victory of her career and her 10th of the season on Friday, said the race provides valuable preparation for the Tour de France Femmes, the biggest event on the women's cycling calendar.
Race director Czesław Lang voiced disappointment that Poland's leading female cyclist, Katarzyna Niewiadoma, winner of the 2024 Tour de France, was not competing, saying the route lacked the mountainous terrain that suits her strengths.
Tour de Pologne race director Czesław Lang. Photo: PAP/Maciej Kulczyński
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Source: IAR, PAP, TVP Sport