Members have backed amending its constitution following an extraordinary general meeting in Essex.
The vote comes after the Central London County Court told the party to alter its constitution to comply with race relations laws or face legal action by the Equality and Human Rights Commission (EHRC).
After the hearing on January 28, the BNP sent letters to its 14,000 members in order to allow for the 14 days needed to alert them to the proposed changes.
Speaking after the vote, BNP leader Nick Griffin told Sky News: "Fundamentally we previously had an ethnic-specific membership policy - you had to be indigenous British to join.
"We've had a number of members of ethic minorities, very close to us, friendly with us, working with us, who weren't able to be members.
"That's been the rule for the party since 1982."
We're happy to accept anyone as a member, providing they agree with us that this country is and should remain fundamentally British.
BNP leader Nick Griffin
He said: "As of today, that's changed. Anyone can become a member of this party.
"We're happy to accept anyone as a member, providing they agree with us that this country is and should remain fundamentally British."
Mr Griffin said he was anticipating a "trickle, rather than a flood" of applications from black and Asian people.
He also said he expected to welcome the party's first non-white member, a Sikh called Rajinder Singh, soon.
He said: "I will be absolutely delighted to shake his hand and give him his membership card."
Mr Griffin went on to say he expected the party's new constitution would be presented to the commission by Tuesday.
It will then have a week to respond and both parties will return to court early next month.
A spokeswoman for the commission said: "We haven't yet seen what the changes are, but hope that the BNP's revised membership policy is no longer discriminatory."
