Quitongo, whose father Jose played for Hearts and Hamilton Academical and brother Jai is currently with Queen’s Park, played the full 90 minutes of the goalless draw at Firhill.
In a statement, Airdrie said: “We can confirm that the club are conducting an investigation into alleged racist remarks made by a supporter.
“As a club, Airdrieonians will not tolerate racism. Any individual using racist language is not welcome at Airdrieonians FC and will face a lifetime ban from attending matches.
“Rico Quitongo has the full support of everyone at the club. Many of our supporters have contacted the club directly expressing their support and respect for Rico.”