Last month, the Daily Telegraph reported that only 10-15% of players in the WSL are from BAME communities.
"Our game is very white, and that has to change. We have to look at what the barriers and challenges are," former England defender Stoney told Sky Sports. "We have to make sure everybody feels this is a game for them.
"We need visibility, so people can see role models within the game. If you can't see it, you can't be it. Equality and diversity is something we have to improve drastically.
"You look across the top WSL clubs, you can count on one hand the amount of Black and minority ethnic players there are in the game. That's got to change."
Diversity in the women's game became a big topic last month when England named an initial 23-woman squad for their Northern Ireland fixture and not a single BAME player was selected.
"I don't want players to feel they can't come to my football club [because of the colour of their skin]," Stoney added.
"We need to encourage all players into the game. If I don't see people like me, there is probably a fear to come into that environment.
"We need role models. The game has come a long way -- an awful long way. We have a fully professional WSL, the standard of the women's game has gone to another level. We are getting more coverage, but the game is still growing."