The Maryland State Board of Education named a former Queen Anne’s County schools chief on Thursday as the interim state superintendent of schools.

Bernard J. Sadusky, who served as chief of the 8,000-student system from 1994 to 2007, will temporarily replace Nancy S. Grasmick, the longtime state superintendent who is retiring June 30.

Sadusky, who has been the state’s liaison to local school districts, will serve in the post while the state board conducts a national search for a new superintendent. He said he will not be the permanent superintendent.

There is no timeline for a replacement, but officials said they expected the search to be exhaustive and deliberate. It is the first time in two decades that the board has had to look for a new superintendent. Grasmick, who took office in 1991, is one of the nation’s longest-serving state schools chiefs.

Sadusky said his prime responsibility will be to focus on the state’s Race to the Top program, including an effort to build a “transparent and fair” teacher evaluation system with a $250 million federal grant. The state recently applied for a 12-month extension to implement the new evaluations after struggling to create such a system.

“Job number one must be to maintain our educational progress,” he said. “My plan is to continue the work that the state board and Dr. Grasmick have started.”

He also plans on zipping around to various schools in Maryland, much like Grasmick, to maintain a constant interaction between the state government and local schools.

Sadusky spent 30 years in the Queen Anne’s school system, starting as a middle school math and science teacher. He resigned as the county’s superintendent in 2007 to work with Grasmick.

Said Grasmick: “I leave my post with great certainty that our public school system is in very good hands.’’

James H. DeGraffenreidt Jr., president of the State Board of Education, called Sadusky “the right leader for this transitional period.”