Kenya's high court has ordered the country's education authorities to amend the name on a school certificate of a woman who was born male.
The name should be changed from Andrew Mbugua to Audrey Mbugua, it ruled.
Audrey Mbugua has been battling to get recognition to live as a woman, says the BBC's Robert Kiptoo in Nairobi.
This is a significant ruling for the transgender community in Kenya, a country with conservative views towards sexuality, he adds.
"We won. It's a huge watershed moment," Ms Mbugua told the Thomson Reuters Foundation.
The court gave the National Examinations Council 45 days to comply with the order to to change the name on her high school exam certificate, without marking her gender.
Judge Weldon Korir said the council had failed to demonstrate why it could not make the changes she desired.
The transgender activist had stunned many Kenyans with her decision to be recognised as a woman, our correspondent says.
The court ruled that Ms Mbugua will have to pay for any extra costs incurred by the council to make the change.
This is Ms Mbugua's second legal victory.
In July, the high court ordered the authorities to register her lobby group, Transgender Education and Advocacy, saying their refusal to do so had no legal basis and was an abuse of power.