Fu Hongyu, the Communist party commissar of the Ministry of Public Security's Border Control Department, said the extra security would "fully protect the stability of Tibet's frontier region".
"To address stability protection in Tibet, we have deployed troops to strengthen controls along the Tibetan frontier at points of entry and on key sectors and roads".
Tuesday marks a half century since Tibetans rose against Chinese rule, triggering what exiles say was a Chinese military response that killed 80,000 people.
Police moves to block a march led by Buddhist monks to commemorate the 1959 uprising in Tibet's main town of Lhasa last year led to anti-China protests and a crack down by the authorities.
Exiles estimate that more than 200 people were killed last year but China denies that it used violence, saying instead that rioters were responsible for nearly two dozen deaths.
In Dharamshala, the Indian town where Tibet's government in exile sits, police have beefed up security amid fears that Tibetan groups could ignore appeals by the Dalai Lama, the Tibetan spiritual leader, for restrained commemorations.
Nepal has also stepped up security by increasing police patrols along its border with China.
Call for unity
Meanwhile, the Dalai Lama has called on all sects of Tibetan Buddhists to unite against Chinese rule.
|The Dalai Lama has urged all Tibetan Buddhist sects to unite [EPA]
"Now we are in such a state where all the people following Tibetan Buddhist traditions and Tibetans-in-exile should be united," he said at a religious conference in northern India on Sunday.
"Otherwise if you remain isolated from one another then the forces, the strength of the unity is lost. So then how can we possibly achieve our goal of Tibetan struggle?"
A German newspaper on Friday quoted the Dalai Lama as saying that the situation in Tibet was very tense and that he feared an "explosion of violence" as the Himalayan region prepared to commemorate the anniversaries.
"Many Chinese citizens have armed themselves, and they are ready to shoot," he was quoted as saying on the website of Frankfurter Rundschau.
"It is a very tense situation. At any moment there could be an explosion of violence."