Brandon Michael Bielak (born April 2, 1996) is an American professional baseball pitcher who is a free agent.

He has previously played in Major League Baseball (MLB) for the Houston Astros and Oakland Athletics.

[2] Undrafted out of high school in the 2014 MLB draft, he enrolled at the University of Notre Dame where he played college baseball for the Fighting Irish.

[7] Bielak signed with Houston and made his professional debut with the Gulf Coast League Astros.

After two scoreless appearances, he was promoted to the Tri-City ValleyCats where he finished the season with a 1–1 record and a 0.92 ERA in eight games (four starts).

[8] In 2018, Bielak began the season with the Buies Creek Astros and was named a Carolina League All-Star; he was promoted to the Corpus Christi Hooks in June.

[11] In 2019, Bielak returned to Corpus Christi to begin the season and was promoted to the Round Rock Express in May.

[16] Bielak made five appearances for Houston in 2022, spending the majority of the season with the Triple-A Sugar Land Space Cowboys.