Ronald Noble said potential attacks could involve efforts to block transportation routes, interfere with competitions, assault athletes or destroy property during the Olympics.
Chinese officials have said that terrorism is the biggest threat to the Aug. 8-24 Olympic Games and has called for closer international cooperation to prevent possible incidents.
"When thwarted attacks are coupled with the recent violent protests viewed by us all worldwide, prudence requires us to recognize the real possibility that groups and individuals could carry on their protests at the actual Games," said Noble, who spoke at an international security conference. His remarks were released in a statement by the Lyon, France-based Interpol.
China's generally secretive police agencies have sought advice on Olympic security from the United States, Germany, Israel and other foreign governments.
Interpol has promised to send a support team to the Olympics that will have rapid access to the international police organization's files on fingerprints, images and wanted persons notices. It will also provide threat assessments related to Olympic security.
"It is our shared responsibility to work together to prevent incidents of crime and violence through preparation and planning," Nobel said.
Experts say the terrorist threat to China at the Olympics is relatively low, but warn that Beijing faces a growing threat from Islamic separatists among the Uighur population in the western region of Xinjiang.
State media reported in March that a 19-year-old Uighur woman was detained after trying to set a fire in an airplane's bathroom in an attempt to hijack and crash the flight. No one was injured and the plane was diverted.
Authorities have said the attempt was part of a terror campaign to turn the predominantly Muslim Xinjiang into an independent nation called East Turkestan.
Earlier this month, Chinese police announced that they had uncovered a criminal ring that planned to kidnap athletes, foreign journalists and other visitors at the Beijing Games.
A Public Security Ministry spokesman said the "violent terrorist gang" was based in Xinjiang but provided scant evidence. He said another ring uncovered in January was manufacturing explosives and plotting to attack hotels, government offices and military targets in Shanghai, Beijing and other cities.
China has been battling a public relations nightmare as the Olympic torch makes its way around the world before returning to Beijing in May.
At nearly every stop on its trek, the relay has been dogged by protests against China's human rights record, its friendly ties with the Sudanese government and its crackdown in Tibet after anti-government protests turned violent on March 14.
In Japan on Friday, police escorted the flame to the mountain resort of Nagano - where the 1998 Olympics were held - under heavy security after it landed at a Tokyo airport.
The Falun Gong spiritual movement, banned in China as a dangerous cult, held a morning protest in a park near the Nagano train station. In the afternoon, a small group of other protesters waved "Free Tibet" banners.
China's government agreed on Friday to a meeting with an envoy of exiled Tibetan leader the Dalai Lama, a step that follows weeks of calls from world leaders for dialogue in the wake of anti-government protests in Tibet.
"In view of the requests repeatedly made by the Dalai side for resuming talks, the relevant department of the central government will have contact and consultation with Dalai's private representative in the coming days," the official Xinhua News Agency said, quoting an unidentified official.