The 20-year-old singer popped the question to a lucky supporter who was dressed as a bride after he picked her out of the sell-out crowd, reported Contactmusic.
While the boy band were thanking the audience at the end of their gig, Styles said: "I heard there was a girl here in a wedding dress ... Is there a girl here in a wedding dress?
"Now I feel bad letting this go to waste so what's your name? Preeya? Preeya ... Will you marry me? There's been a plot twist! OK .. Awesome," Styles said.