Douglas, who took part in the all-around gymnastics competition on Thursday (August 2), is the first African-American to take gold in the event.
After her victory, the broadcast went to a commercial break, which showed a clip for upcoming sitcom Animal Practice, starring a monkey in a gymnastics uniform performing on the rings.
The timing of the commercial sparked anger from Twitter users, with some calling the network "racist" and "awful" for showing it immediately after Douglas received her gold medal.
However, NBC has since made a statement to the Daily Mail claiming that it did not intend to cause offence, saying: "Gabby Douglas' gold medal performance last night was an historic and inspiring achievement.
"This spot promoting Animal Practice, which has run three times previously, is one in a series with an Olympic theme which have been scheduled for maximum exposure. Certainly no offence was intended."
The 16-year-old was congratulated by Beyoncé in a post on the singer's official website on Thursday.
Rapper Lil Wayne also tweeted his support for Douglas, calling her an "icon".
London 2012 Olympics - rolling gallery: