In December, Minister of Health Andrew Little said the change was not about condoning the use of drugs by young New Zealanders.
"We would prefer they didn't. But the evidence is that when allowed to operate, drug-checking services can significantly reduce drug harm."
There has also been concern over the summer about bath salts being sold as MDMA.
OUSA chief executive Debbie Downs said drug checking was in line with the association's harm prevention strategy.
Drug testing was also available at both the 2019 and 2020 Orientation events.
Last year, 25 samples were tested over three days and 12 per cent of those turned out not to be the drug the person believed it was.
Twenty of the samples were MDMA, one sample was ketamine, and two were LSD.
This year's Orientation events will be held at the Union Hall and Starters Bar, in a departure from recent years, when they have been hosted at Forsyth Barr Stadium.