The 36-year-old ride was closed down April 13, along with the Soarin' Over California and Matterhorn rides, after state regulators found safety procedure and equipment violations, the Los Angeles Times reported Friday.
The California Division of Occupational Safety and Health was investigating the Space Mountain ride after a contract worker was injured in a fall in November. Another worker, a machinist, was critically injured a month earlier when he was hit by a speeding vehicle during tests for the ride, the newspaper said.
The state regulator fined Disneyland $234,850 for six violations relating to the maintenance of fire extinguishers, safety barriers and anchors for exterior cleaners of the ride, the Times reported.
Disneyland officials said Space Mountain was reopened for rides Friday evening.
The Soarin' Over California and Matterhorn rides had already been reopened.