The suit says Google is aware of the situation, but has not moved to fix it.
It comes as companies in Silicon Valley face growing scrutiny over gender relations.
Google is also under investigation by the US Department of Labour over its pay practices.
"It is time to stop ignoring these issues in tech," said Kelly Ellis, a former software engineer at Google and one of the women who filed the suit.
She posted on Twitter that she hopes the suit will force Google and other companies to change their practices.
