The diva was nearing the half-time interval in her concert when a middle-aged woman seated downstairs fainted.
St John personnel attended to the woman, who was "rather embarrassed when she came round", festival director Nicholas McBryde said yesterday.
"It was quite hot in there and she fainted heavily, which caused a wee bit of a kerfuffle and some disruption to Dame Kiri.
"We had to turn the house lights up so we could see what was going on," Mr McBryde said.
Dame Kiri briefly talked to the crowd about her shopping trip to the Otago Farmers Market, before leaving the stage with accompanist Terence Dennis.
She returned after about five minutes.
It was Dame Kiri's first solo recital in Dunedin.