Staff at an Auckland restaurant have been put on "umbrella watch" after a complaint that diners are stealing Blunt umbrellas.

Diners at PappaRich Malaysian restaurant in Aotea Square have to leave their wet umbrellas at the counter but a man who left his $170 Blunt umbrella there last week, returned to find it gone. The only umbrella there was a "$2-shop-type" small red polka-dotted one.

"I've asked my supervisors to keep an eye out," said PappaRich managing director Steven Loh.

The area where umbrellas are left is now under camera surveillance.

"If the incident is less than three days, we can review the footage," Loh said.

He said no one else had complained about umbrella thefts.

The man who lost his umbrella believed Blunt umbrellas are now the target of thieves because of recent wet weather.

Blunt is advertised as a high-performance umbrella that's "made to last" and a "must-have companion for day-long downpours".

The umbrellas are made to withstand winds of 117km/h - but is no match thieves in Auckland.

"My umbrella is supposed to be made to last and even comes with a five-year warranty, but I guess it doesn't last when you're dining out in Auckland," said the man, who didn't want to be named.

He bought his Blunt just a month ago when the weather in Auckland "started going crazy".

A police spokeswoman advises people to mark property they consider to be valuable.

"Thieves are unlikely to steal items that are permanently marked because they're hard to sell," she said.

"Portable items of high value are the most likely things to be stolen."

The spokeswoman said keeping receipts and warranties would also help prove ownership of the stolen items for insurance claims.