The 45-year-old will be assisted by fellow Poles Tomasz Listkiewicz and Adam Kupsik as linesmen.
Meanwhile, New Zealand's Campbell-Kirk Kawana-Waugh will serve as the video assistant referee (VAR), Polish state news agency PAP reported.
The tournament marks Marciniak's third World Cup as a referee. He previously officiated at the 2018 World Cup in Russia and the 2022 World Cup in Qatar.
In Qatar, he took charge of the final, in which Argentina defeated France on penalties after a 3-3 draw.
Marciniak has also officiated at two European championships, handling three matches at Euro 2016 in France and two at Euro 2024 in Germany.
The 2026 World Cup, co-hosted by the United States, Canada and Mexico, kicked off on Thursday and runs through July 19. The expanded tournament features 48 teams, up from 32 in 2022.
Poland failed to qualify after losing 2-3 to Sweden in a playoff final in March.
(gs)
Source: IAR, PAP