Drysdale, fresh from his World Cup gold medal in Munich last month said the hard work over New Zealand's summer was paying off.
"The really surprising thing is how nice it is to come to Europe and be ahead of everyone else so early. And there's still a lot more to come. I'm happy with the way I started," he said.
"This is only the second time I've come straight to Europe and won. Usually I'm straight into the medals and improve as the season goes on. This time I'm confident I can get better. When you start ahead you can keep getting better."
Olympic bronze medallist Drysdale is in the Diamond Sculls at the classic English regatta, competing against compatriot Duncan Grant, former double Olympic champion Olaf Tufte, fast-starting Briton Alan Campbell and Belgian Tim Mayens.
"Henley is really important especially this year because all the top scullers are here," Drysdale said.
"Four out of the Olympic top five are here so it's a very strong field. We all want to come away with the win."
The regatta is a highlight of the English social calendar, which added to mystique for Drysdale.
"I love Henley. It's one of my favourite regattas. It's unique and prestigious and obviously a different format.
"It's the oldest regatta of racing goes tight back to the 1840s and is something very special to win.
"I got beaten a couple of years ago by Alan Campbell so will go out to get revenge for that. It's a unique atmosphere -- different to anything else. There's even a few different rules like you race one on one."
Drysdale heads a strong New Zealand group including lightweight double scullers Storm Uru and Peter Taylor, and Nathan Cohen and Peter Taylor in the Challenge Cup while Emma Twigg and Juliette Haigh are both in the Princess Royal Challenge Cup for single scullers.
Men's pair Hamish Bond and Eric Murray are in the Silver Goblets and Nickalls Challenge Cup, while Emma-Jane Feathery, Rebecca Scown, Paula Twining and Anna Rayner form a quad for the Princess Grace Challenge Cup along with another foursome -- Genevieve Armstrong, Louise Trappitt, Harriet Austin and Sarah Barnes.
