Addressing neighbouring countries at a summit, Mr Xi also said that issues and problems in the region should be resolved by Asians themselves.
His comments come as the United States seeks to increase its presence in Asia. China is locked in disputes with several neighbours over claims in the South China Sea.
The Philippines, which has accused China of building an airstrip on a disputed reef, recently hosted President Barack Obama, who pledged "ironclad" support for the US ally. Mr Obama also made stops in Malaysia, South Korea and Japan on his tour last month.
Speaking at the Conference on Interaction and Confidence Building Measures in Asia (Cica) on Wednesday, Mr Xi said: "Strengthening military alliances with a third party does not benefit the maintenance of regional security."
"Matters in Asia ultimately must be taken care of by Asians, Asia's problems ultimately must be resolved by Asians, and Asia's security ultimately must be protected by Asians," he said.
Mr Xi said each country should play its part in preserving regional security. "A country, in seeking to determine its own security, should not sacrifice that of other countries... no country should seek to monopolise regional security affairs and trample on the rights of others," he said.
He added that such a situation would do no good as "a Kazakh saying goes: Blowing out another's lamp will only burn one's beard" Mr Xi proposed that Cica, which has 24 member nations, become a security dialogue platform, and that it establish a "defence consultation mechanism", with a response centre for emergencies.
The Chinese president was speaking to delegations from more than 40 countries and organisations. These included Vietnam's Vice-President Nguyen Thi Doan and representatives from the Philippines and Japan.
The presence of a Chinese oil rig in waters also claimed by Hanoi sparked a wave of anti-China protests across Vietnam earlier this month which left at least two Chinese workers dead and factories burnt.
The Philippines, meanwhile, is taking China to an international court over its South China Sea claims.
