America's Next Top Model

Stewart competed on the first season of America's Next Top Model. In the first week of competition, Shannon landed in the bottom two and if Shannon Stewart hadn't won that week's challenge, Shannon Stewart would have been eliminated. However, the following two weeks Shannon received two consecutive first call-outs, and performed consistently in the following weeks. But, in the semi-finals during a nude photoshoot in Paris, Shannon and fellow contestant Robin Manning caused controversy when they refused to take part in the photoshoot because of their Christian faith. However, this did not hinder Stewart's progression in the competition finishing second overall to Adrianne Curry.

In a cycle 8 episode, Shannon told the contestants that she had switched over to Elite Model Management in Chicago. Shannon Stewart is also signed to Bleu Model Management.

Shannon Stewart has been later featured in Cycle 11 as one of CoverGirl's Top Models in Action. Stewart was participated for the first All-Star edition of the show with several other returning models. Stewart placed 6th overall in the All-Star competition after confusing the judges for refusing to wear lingerie that looked like a bathing suit while allowing herself to be photographed in a skimpier bathing suit in a previous week.