The immediate shutdown is in line with China's zero-tolerance pandemic approach, which seeks to stamp out local outbreaks as swiftly as possible.
Since the pandemic began, China has reported 4,636 deaths and 97,243 cases.
One Disneyland fan, who gave her last name as Chen, was in the park during the 5 pm announcement that everyone had to be tested.
"No-one complained, and everyone behaved really well," said Chen, who holds an annual membership to the park and visits at least once a month.
Chen told local media she was waiting at a hotel for her second Covid-19 test result before being allowed to return to Beijing.
Similarly, a train travelling from Shanghai to Beijing was halted mid-journey after one passenger was discovered to be a close contact of a Covid-19 case.
All passengers were quarantined by police and health workers while the train was disinfected.
China continues to maintain extremely strict quarantine and entry requirements for both residents and visitors travelling into the country.
