Jose Miguel Vivanco accused Mr Chavez of weakening democracy
Venezuela has expelled two key Human Rights Watch activists for a report that criticised the country's rights record under President Hugo Chavez.
The foreign ministry said Jose Miguel Vivanco, HRW's Americas director, and his deputy Daniel Wilkinson had committed "serious violations".
Earlier on Thursday, the two men issued a report that accused Mr Chavez of weakening democracy in Venezuela.
The move follows a series of tit-for-tat expulsions with the US.
Mr Chavez expelled the US ambassador last week in support of Bolivia's President Evo Morales, who threw out the US envoy in La Pas after accusing Washington of trying to oust him.
In response, Washington has expelled both the Bolivian and Venezuelan ambassadors.
In a televised statement, the foreign ministry said Mr Vivanco had "violated the constitution and the laws" of Venezuela and "illegally interfered in the country's internal affairs".
Foreign Minister Nicolas Maduro said Mr Vivanco, a Chilean, had left the country. It was not immediately clear if Mr Wilkinson had gone too.
The expulsion "is a clear message to whoever intends to come here and plot from within", Mr Maduro said.
Hours earlier, Mr Vivanco and Mr Wilkinson held a press conference to present their report "A Decade Under Chavez: Political Intolerance and Lost Opportunities for Advancing Human Rights in Venezuela".
Mr Vivanco said Mr Chavez had "weakened democratic institutions and human rights guarantees" during his decade in power.
"Discrimination on political grounds has been a defining feature of the Chavez presidency," the report said.
The government "has tolerated, encouraged and engaged in wide-ranging acts of discrimination" against its opponents, it concluded.