Figures produced by the Scottish government show 97.1 per cent of Shetland patients attending the Gilbert Bain Hospital in Lerwick were seen within four hours during the week up to 4th July.
The only health board to achieve better results was Orkney at 97.8 per cent.
Nationally, 81.6 per cent were seen within four hours, compared with a target of 95 per cent.
Highlands and Islands MSP Jamie Halcro Johnston said Shetland and Orkney’s performance was “welcome news” and praised staff.
However, he also said the national figures were concerning and highlighted the Scottish Conservatives’ calls for a one-off £600 million investment to tackle waiting times.
“SNP Ministers should consider backing our plans, as well as looking at the self-isolation rules for fully vaccinated NHS staff to reduce the risk of key departments within our hospitals being left under-resourced,” he added.