WA women are more than $400 a week behind their male counterparts as they continue to struggle to get the best-paid jobs.
Figures from the Australian Bureau of Statistics reveal the average male wage across WA was $1745 a week in the three months to the end of November.
It gave men an average annual wage of $91,213, the highest of any State or Territory.
But WA women found their pay packets much lighter at an average of $1338 a week, or $69,586.
The gap between male and female wages - more than $400 a week - is the biggest in the country.
The next biggest is in Queensland, where the gap is $317 a week. The smallest is in Tasmania at $141.
Much of the difference is driven by the male-dominated mining sector.
A man working in mining has an average wage of $2553 a week.
The female-dominated retail trade sector has an average wage of just $1091 a week but women average a weekly pay packet of $950.
The figures come after this week's wage price index showed pay rates increased at their slowest rate this century in 2012.
CommSec economist Savanth Sebastian said the figures also showed how the slowdown in the mining sector was now flowing through to wages.
"Wages in the mining sector are now almost 2½ times the earnings in the retail sector as well as food sectors like cafes and restaurants," he said.
"Interestingly while the resources States of WA, the Northern Territory and Queensland were dominating in the pay stakes, the growth in wages actually went backwards over the past year - once again as a result of the pullback in mining investment." Only the wages of men in the ACT are close to those in WA, about $15 a week lower.
But WA women earn about $250 a week less than their counterparts in the public service-focused ACT.
And the gap between WA women and their counterparts in other States and Territories is much smaller.
The gap between women working in WA and NSW is about $40 a week.