Men typically earn £3,794 annually from their investments, compared with £2,422 for women, according to research by private equity investment specialist Radius Equity.
The suggested reasons for this are a combination of women tending to have less income to put into investments because of the gender pay gap, and that the investments they take out often reflect a perceived lower appetite for risk than men.
Missing out: Women earn an average of £1,372 less than men every year on their investments
The company analysed figures from Her Majesty's Revenue & Customs that show men are 20 per cent more likely than women to invest in a stocks and shares Isa.
Investing in an Isa brings a greater risk but also typically a higher return than a cash Isa.
Of the women who took up an Isa in the 2012-2013 tax year, 5.9million or 82 per cent of chose to go for a cash-only product.