The regulator said that it received 331 complaints after Friday's semi-final, with around half complaining that ten-year-old singer Hollie Steel was allowed a second chance to perform, and approximately 50 expressing concerns about her welfare.
Of the 16 complaints received after Saturday's final, most regarded the performance of the eventual winners Diversity.
Ofcom said: "With Britain's Got Talent, we are reviewing the complaints we have received against the Broadcasting Code.
"As with all such cases, our assessment will help us to decide whether we need to investigate or not; however, at present we are not investigating."
Culture secretary Andy Burnham has suggested that the watchdog should investigate the off-show care of Boyle by ITV bosses.
Boyle is currently being treated at the Priory in London after she was admitted to the clinic on Monday.