Minogue admitted that she now sings the track, which reached number two on the UK singles chart in 1990, in a lower key for performances as the original is too high for her voice.
In an interview with Elle, she said: "Better the Devil You Know' was a turning point and an exciting time for me. I was 21, I'd just started dating [Australian singer-songwriter] Michael Hutchence and a different world had opened up.
"That song is ludicrously high, so when I perform it on tour, we take it down a bit. Some of those songs sound simple, but when you tackle them live, they're not easy."
Minogue's new single 'All The Lovers' makes its radio premiere on May 14.