The politicians call on ASDA's majority owners TDR Capital, headed up by Manjit Dale and Gary Lindsay, to settle the legal battle which has seen tens of thousands of supermarket workers bring their equal pay case to the Employment Tribunal.
The letter, which comes as Asda hosts drinks at Labour conference, is signed by 159 Members of Parliament and points out 'women workers on the shop floor earn up to £3.74 per hour less than their male counterparts in warehouses.'
Asda's retail workers are currently owed more than £2 billion in back pay, it adds.
At least 60,000 predominantly female Asda supermarket workers have been locked in a 12 year legal tussle to be paid the same as the predominantly male warehouse workers.
The second stage of the hearing is currently being heard in the Manchester Employment Tribunal.
Supermarket workers roles have been independently assessed as being equivalent or equal to the work of warehouse workers, meaning the roles should be paid equally.
Nadine Houghton, GMB National Officer, said:
"GMB members working in Asda stores will be delighted to know that politicians support their cause.
"Low paid women workers have propped up the profits of retail giants for too long, its time they are paid properly for the valuable work they do.
"The courts and now politicians are waking up to the scale of discrimination faced by women retail workers and now Asda's owners have a chance to do the right thing and pay them what they are owed."
