The Waratahs scored six tries to two in Sydney to rout the Highlanders, who played much of the match with 14 men after winger Tevita Nabura was sent off in the 19th minute for foul play.
The last time an Australian team beat a New Zealand side was just over two years ago when the Waratahs downed the Chiefs.
The Waratahs began full of intent and opened an 8-0 lead after 14 minutes thanks to a Bernard Foley penalty and a try to massive winger Taqele Naiyaravoro.
They took complete control once Nabura inexplicably kicked NSW winger Cameron Clark in the head as he leaped for a high ball.
Three minutes later the visitors were down to 13 men when Aaron Smith was shown a yellow card for a deliberate knock-on.
The Waratahs only scored once during Smith's 10 minutes in the sin bin, a second to Naiyaravoro, but they dominated the first half and took a 15-0 lead into the break.
Israel Folau scored the 49th and 50th tries of his Super Rugby career in the opening stages of the second half as the Waratahs began to run away with the match.
The Highlanders scored twice but two more Waratahs tries underlined a dominant NSW win.
"The last thing we'd been thinking about (was the losing streak)," Waratahs captain Michael Hooper said.
"We'd been thinking about what we've been doing each week, incrementally building, and we got a good result tonight," he said.