The Environmental Protection Agency was ordered by a federal judge here yesterday to require states to reduce emissions of sulfur dioxide and other pollutants that cause acid rain.

The ruling by U.S. District Court Judge Norma Holloway Johnson came in a suit against the EPA by six northeastern states, led by New York. They charged that the agency failed to take proper action against the pollutants following a determination that they caused harm in both the United States and Canada. The finding was issued by former EPA administrator Douglas M. Costle during the last week of the Carter administration.

Last December the EPA turned down a petition seeking the emission controls in seven midwestern and northern border states. The agency said more tests were needed to determine the source and effects of acid rain. That decision is under appeal in the U.S. Court of Appeals here.

Yesterday's ruling did not specify which states must be subject to the new controls, which would affect mainly power plants and heavy industry. Johnson said that before the agency starts the process of having the states set stricter standards, it has 90 days to review a finding by Costle that Canada gives "reciprocity" to the United States by enforcing similar air pollution standards.