The company, headed by billionaire Elon Musk, opened the showroom in the city of Urumqi on New Year's Eve.
Condemnation followed, but China's Foreign Ministry spokesperson Wang Wenbin accused the critics of "hypocrisy" and said they "carry out economic coercion and political repression against China under the guise of human rights."
On Tuesday, the biggest US Muslim advocacy group, The Council on American-Islamic Relations, urged Tesla to close its Urumqi showroom.
"By doing business in China's Xinjiang Province, where millions of Uyghur Muslims are being held in concentration camps and forced labor facilities, Tesla is supporting genocide," the group wrote on Twitter.
Republican Senator Marco Rubio accused Tesla of "helping the Chinese Communist Party cover up genocide and slave labor in the region."
White House spokeswoman Jen Psaki said she would not comment directly on Tesla's action, she said that the "private sector should oppose the PRC (People's Republic of China) human rights abuses and genocide in Xinjiang."
"The international community, including the public and private sectors, cannot look the other way when it comes to what is taking place in Xinjiang."
Wang on Thursday again dismissed the accusations as "lies that have long been exposed by the facts."
Amnesty: China committing 'crimes against humanity'
But China has previously admitted to keeping Uyghurs and other Turkic-speaking minorities at "vocational training centres" to ensure militant activities are "eliminated before they occur."