The country hopes to increase that figure to 10 per cent by 2030.
Swiss National Council member Marianne told the BBC that offering women more suitable gear would encourage more to apply to join the military.
"The clothing is designed for men, but if the army is really to become more feminine, appropriate measures are needed," she said.
Army spokesman Kaj-Gunnar Sievert told Swiss news website Watson that the new "functional underwear" for female recruits would consist of "short underwear" for the summer and "long underwear" for the winter.
Swiss Defence Minister Viola Amherd has welcomed the move, saying that "compatibility" needed to be improved, according to the BBC.
Here’s how Twitter has responded to the news:
@BBCWorld You're telling me their knives have a hundred options, but when it comes to underwear it's just 1?