The average director of a top company is now paid 85 times as much as the average member of their staff, according to a new report.
The TUC said boardroom pay was increasing year after year while workers' earnings were failing to keep pace with rises in the cost of living.
In a report ahead of a national demonstration in London tomorrow under the banner, Britain Needs A Pay Rise, the TUC said the average director of a company in the FTSE 100 would earn in one day what someone on the living wage of £7.65 an hour would in a year.
Total pay for the highest paid director in the 2012/13 financial year was £31 million - 2,238 times the annual full-time living wage outside London, said the TUC.
TUC general secretary Frances O'Grady said: "While most are suffering continuing cuts in their living standards despite the recovery, boardroom pay just gets bigger and bigger every year.
"Most companies fail to provide proper information on how much their UK staff earn. The government is complicit in this cover up as ministers refuse to make companies publish the kind of information investors and employees need to work out the gap between boardroom pay and the rest.
"These shocking new figures show that it is those at the top gaining from the recovery, while living standards are still falling for the majority. That is why tens of thousands will be marching tomorrow."
The study for the TUC, by researchers at Incomes Data Services, claimed that in the 2012/13 financial year, Simon Peckham, the chief executive of engineering firm Melrose, received more than £3.1 million.
A Melrose spokesman said: "These figures are completely inaccurate. His total salary for the year (to December 2012) was £409,800."
A government spokesman said: "Under this Government we've seen the largest annual fall in unemployment, more people in work than ever before, and this year the first above inflation rise in the national minimum wage since the recession.
"We appreciate that although we are now on the road to recovery, the effects of the recession are still being felt. This is why we have taken continued action to help people by cutting income tax and freezing fuel duty.
"We also want to restore the link between top pay and performance. Recognising that in recent years pay has become excessive and increasingly disconnected, we have introduced comprehensive reforms which give shareholders more power to hold companies to account over what they pay and why."