Women could wait 200 years for equality.
The EOC's annual survey of power jobs in the private and public sector found that just 11% of directors at FTSE-100 companies were female, and women made up only 9% of the senior judiciary.
In the higher echelons of the police the proportion was 10%, although the situation was better among heads of professional bodies, with 33% female.
However, the most striking figures were from the UK's traditional heart of power, with just 20% of MPs women.
At the current rate of change, it would take 40 years to reach an even gender split in top companies and the judiciary, and up to two centuries - some 40 elections - to achieve equality in the House of Commons, says the report.
Jenny Watson, chairwoman of the EOC, called on political parties to use 'positive action' to bring in more women.
She said Tory leader David Cameron had to follow through on his promises to increase female candidates, and workplaces had to become more flexible to accommodate mothers and fathers.
'Thirty years on from the Sex Discrimination Act, it is time for us to face some stark facts. Women will not make it to the top in significant numbers unless action is taken to remove the barriers.'