Somehow, they managed to avoid resorting to reserve parachutes and crash landing.
However, it's understood the woman required hospital treatment for serious rope burns, bruises, and head cuts that required stitches.
The couple are understood to be traumatised by the incident and have not responded to approaches by the Herald.
Australia's Civil Aviation Safety Authority last night said it had not received a report but was seeking information from the Australian Parachute Federation (APF).
Yesterday, an APF spokesman confirmed it was investigating.
"We have been informed of an incident that occurred on Monday," he said.
"The incident involved a collision between two open parachutes. Both parachutes landed safely on target without the need for any emergency parachutes. Further details have not yet been established."
He added: "APF investigate all incidents so as to continually improve safety outcomes."
One experienced skydiver told the Herald that the couple, and the instructors, would've had a major scare.
"I haven't had a mid-air collision - touch wood - but the threat is always something you think about," said the jumper who wanted to remain anonymous.
"They would've got quite the fright. Even with reserve chutes as back-ups, this would've been terrifying, especially with the lines getting tangled around your neck and stuff."
In January, two instructors at a Queenstown skydiving company were seriously injured during a tandem training flight.
Sasa Jojic and Sasa Ljaskevic, both originally from Serbia, hit the ground at Drift Bay, south of Jacks Point, at "high speed" and were lucky to escape with their lives.