Army Secretary Clifford Alexander yesterday made more veterans eligible for burial at Arlington National Cemetery by easing restrictions imposed 10 years ago due to a lack of burial.

By clearing old barracks from 200 acres of adjoining property at Ft. Myers, space for about 100,000 new graves will become available, enoug to last through the year 2008, an Army spokesman said. In addition, a "columbarium" to house 50,000 urns of cremated remains will be ready by next year.

When space at the world-famous cemetery began to run out 10 years ago, eligibility for burial was restricted to Medal of Honor winners, active and retired career military personnel and honorably discharged veterans who also served in high federal government posts. They encompassed about 2 per cent of all veterans.

Under the new rules, which will be effective April 15, veterans with at least a 30 per cent physical disability, holders of medals for bravery, distinguished services or war wounds, as well as their spouses and dependent children, may be buried at the cemetery.

Arlington National Cemetery is the final resting place for more than 169,000 persons, including President Kennedy and his brother Robert F. and the tomb of the Unknown, Soldier. Last year, Richard S. Welch, a Central Intelligence Agency representative who was killed in Greece, was buried there with military honors.

Another national cemetery is being constructed at the Quantico Marine Corps Base south of Washington, which is expected to be completed by 1979 and have room for 300,000 veterans.

The conversion of the 200 Ft. Myer acres to the cemetery has been under way for sometime, a spokesman said, and the eligibility restrictions were eased as soon as the space became available. Survivors of persons believed to be eligible for burial in Arlington National Cemetery mush show the Army documents to prove that their relatives are eligible.

Space cannot be reserved in advance, the spokesman said.