The South Korean government released 14 convicted dissidents today before completion of their sentences in what appeared to be the first easing of the tight political role imposed two years ago by President Park Chung Hee.

Prosecutor General Oh TakKun announced the names of those freed and said more releases could follow.

An estimated 150 dissidents, the most prominent of whom is opposition leader Kim DaeJung, remain in prison convicted of violating Park's emergency decree of May 1975 banning criticism of the president and his government.

Oh said that the releases were made by suspending the prisoners' sentences, which means they could be sent back to jail if the government considers them to be violating the past wrongdoing.

The Rev. Yun BanUng, a Presbyterian minister, and Father Shin Hyun Bong, a Roman Catholic priest, headed the list of those freed. Each had received a three-year sentence in connection with a "Manifesto for Democracy" issued in March 176.

The others were six college students, two office clerks, two farmers and two persons without jobs. Their sentences ranged from one year to 2 1/2 years.

Their release came on South Korea's 29th Constitution Day and 10 days after the National Assembly unanimously adopted a resolution urging Park to seek national harmony by lifting the emergency decree and freeing dissidents.

Since coming to power in 1961, Park has followed a policy of increasing repression interrupted by brief periods of liberalization. In the past, student riots and significant growth in opposition activities have prompted Park to call off his relaxation of controls.

Any easing of Park's rigid rule is expected to be welcomed in Washington as consistent with president Carter's human rights policies. If the thaw continues, however, it is more likely to be bound up with internal political developments rather than any desire to please an American President already pledged to remove 33,000 U.S. ground troops over the next four or five years.