Mirnyi and Czech Andrea Hlavackova will meet American Abigail Spears and Mexican Santiago Gonzalez on Arthur Ashe Stadium.
The seventh-seeded Mirnyi and Hlavackova reached the final by defeating Wimbledon mixed doubles champions Kristina Mladenovic of France and Daniel Nestor of Canada 7-5 6-7 12-10.
The 36-year-old Mirnyi is chasing the 10th major doubles title of his career.
He partnered with Serena Williams to win the US Open mixed doubles crown in 1998 and was triumphant again in 2007 with Victoria Azarenka.
Mirnyi's impressive resume also includes an mixed doubles Olympic gold medal he won with Azarenka in London last year.
Spears and Gonzalez defeated fifth seeds Anabel Medina Garrigues of Spain and Bruno Soares of Brazil 6-3, 6-1.
Spears, 32, will contest her first Grand Slam final in 63 attempts.
- Sports & Recreation
- Abigail Spears
- Serena Williams
- Andrea Hlavackova
- Victoria Azarenka
- Kristina Mladenovic
- Arthur Ashe Stadium