The commission is concerned that employers will find it increasingly difficult to find high-quality IT staff as the number of women in the profession continues to dwindle.
The proportion of women in the IT workforce fell from a high of 23% to 20% in 2003 - equivalent to 151,000 women out of a total workforce of 985,000 - research by the Equal Opportunities Commission reveals.
The equality watchdog has called for the government to create a national strategy that will set clear targets for increasing the number of women in IT and other male-dominated professions.
"This is a significant issue that affects everyone throughout the economy. A workforce recruited from only half the potential source of labour does not deliver the best workers," the Equal Opportunities Commission said.
The commission pointed to the lack of flexible working hours and a shortage of child care facilities as barriers to women entering the IT profession. Workplace culture and the poor image of IT also act as deterrents, it said.
The careers information and advice offered to young people often reinforces gender stereotypes and fails to present the full range of employment options open to men and to women in the technology industry, the organisation said in a report published this month.
The Equal Opportunities Commission urged the government to use the Modern Apprenticeship programme, currently under-used by IT employers, as a vehicle for encouraging more women into the profession.