The shop's back door was only 10m from Victoria St, where the royal procession passed huge crowds yesterday.
The store is 100m from the town hall, where the royal couple stopped for lunch, and 60m from the war memorial where William and Kate each laid a rose.
Several monitored alarms were triggered during the break-in.
Witnesses who saw two people wearing hoodies in the store alerted police.
Police say the break-in was coincidental, and not a royal-tour security breach. The store was searched and secured after the break-in.
Waikato police spokesman Andrew McAlley did not believe the thieves were taking advantage of police attention being focused on the royal tour.
"I think quite the opposite is true, with police able to act quickly because there were so many officers in the area."
Police were investigating reports of a dark-coloured Mitsubishi Galant leaving the scene. A burnt-out car of the same colour and model was found hours later on a rural Cambridge road. Forensic officers were examining the car.
Store owners Andrew and Katrina Haultain said the break-in was highly organised by thieves who knew where expensive jewels were.
"They smashed the back door down and went for higher-value items. They knew where everything was," Andrew Haultain said.
"They took wedding rings, watches, diamond rings, coloured stone rings, Tissot watches, Seiko watches and Pandoro jewellery," he added.
"They smashed and grabbed and only left behind what they couldn't carry."
Katrina Haultain said last night that no one had been arrested but blood was found in the store, probably the result of a thief cutting themselves after smashing a cabinet.
A former head of royal protection for London's Metropolitan police, Dai Davies, caused a furore this week when he blasted Governor-General Sir Jerry Mateparae for publishing details of Kate and William's itinerary.
Last night, Davies said he would not regard yesterday's Cambridge break-in as a security breach, but he stood by his earlier comments.
"You simply can't secure everywhere — but that's the whole point of not disclosing routes."
• Pictures: The royals in Waikato
• Read more royal stories here.
