WA took the top spot from US gold mining state Nevada, which moved down to third out of the 109 jurisdictions assessed.
Uranium and potash hot spot Saskatchewan remained in second place, while Ireland jumped 10 spots into fourth.
In fifth was Finland, followed by Alaska, the Northern Territory (up from 31st), Quebec, Utah and South Australia (up from 16th).
WA Mines and Petroleum Minister Bill Marmion attributed red tape cuts as the reason for the state’s top ranking.
“There is never a bad time to be the world's best, but it is particularly important at this stage in the resources cycle,” he said.
“This is a win-win situation for responsible development and all West Australians. Investor confidence means projects are more likely to get the financial go-ahead, which means more jobs to build Western Australian communities.”
Anonymous quotes from companies surveyed praised WA’s faster approvals, which allowed projects like Sandfire Resources’ DeGrussa copper deposit and Independence Group’s Nova discovery to go from discovery to mine within three years.
"We are processing approvals in record times, while driving new discoveries through our $130 million Exploration Incentive Scheme, WA's significant investment in research and technology, and the creation of Australia's biggest core library," Marmion said.
"The benefits of our world-leading Mining Rehabilitation Fund are also flowing through, cutting costs and encouraging rehabilitation, after returning $1.1 billion to the industry from the old bond system."
Queensland was ranked 16th, followed by Tasmania (30th), New South Wales (38th), and Victoria (62nd).
Industry groups the Chamber of Minerals and Energy of Western Australia and the Association of Mining and Exploration Companies welcomed the result, but said there was more to be done on the policy front.
“Comments from survey participants highlighted the need for improvements in some Australian jurisdictions, especially in New South Wales with regards to approval timeframes and in Queensland with regards to land access and workplace relations,” AMEC CEO Simon Bennison said.
“Whilst Australia as a whole is on top of the world for investment attractiveness, more can be done at the federal, state and territory levels to increase mineral exploration and reduce the operating cost environment.”
The least attractive destination for miners was the Argentinean province of La Rioja, replacing Venezuela, which was the second-worst.
Honduras was considered the third least attractive, followed by Greece, Solomon Islands, Chubut, Guinea (Conakry), Kenya, Mendoza and Rio Negro.
