Several hundred people have gathered in the Kazakh city of Almaty to protest against what they call "Chinese expansionism".
The protest follows the announcement by the country's leadership of a proposal to lease farmland to China.
Kazakhstan shares part of its eastern border with China.
And despite being one of the largest countries in the world it has a population of just 16 million. China is one of its leading investors.
Holding banners that read "Kazakh land is not for sale", between 500 and 1,000 people gathered in one of Almaty's parks.
Addressing the crowd from a platform under a giant statue of Lenin, a group of opposition leaders urged the government to reconsider.
The action follows remarks made by President Nursultan Nazarbayev in December that China was interested in renting a million hectares of farmland from Kazakhstan.
But the announcement has sparked controversy. Protesters say they feel threatened by their eastern neighbour.
"Our people are awakening, our land is under threat," said one.
"I think there should be more people here. People do not fully understand what is around the corner."
Public demonstrations are usually banned in Kazakhstan.
Despite this meeting being sanctioned by the authorities there was a heavy police presence.
The general prosecutor's office has warned that those exploiting the issue of farmland to incite ethnic tension could be charged.
China is a leading investor in oil-rich Kazakhstan. Last year it lent $10bn in credits in exchange for stakes in one of Kazakhstan's largest oil companies.
BBC News - Kazakhs protest against China farmland lease