CLEMSON, S.C. (AP) _ Clemson University on Monday selected the head of Ohio State University's agriculture department as its new president, less than four months after Bill Atchley left the post amid controversy over the role of athletics at the school.

Trustees voted unanimously in closed session for Max Lennon, vice president for agricultural Administration and executive dean for agriculture, home economics and natural resources at Ohio State, said board of trustees chairman Louis Batson.

Lennon, 45, said he expected to begin his new job as president ''fairly early'' after Jan. 1. Lennon earned his associate degree from Mars Hill, and his bachelor's degree and doctorate from North Carolina State University.

The names of the other candidates, at their request, were not disclosed.

Clemson has been wrangling with a series of controversies rooted in the athletic department that eventually caused the resignation of Athletic Director Bill McLellan and, some say, contributed to Atchley's resignation.

First the basketball program was put on probation by the NCAA for rules violations. Then, after a national championship in 1981, the football program was penalized for improper recruiting.

Then came a drug scandal - a state investigation earlier this year determined that three coaches were illegally dispensing prescription drugs to athletes to improve their performances.

Atchley resigned as president in March and left the school July 1, citing the board's refusal to let him restructure the athletic department.

McLellan resigned a few months later.

Melvin Barnette, vice president in charge of business and finance, was asked to resign in July and left the school last week. One of the reasons for his dismissal was his failure to tell Atchley of an in-house investigation of the drug dispensing.

Lennon, in discussing his appointment, stressed that athletics would hold a subordinate role to academics.

''We're obviously very proud of the significant accomplishments of the academic community as well as the athletic community,'' he said. ''''We will strive very hard to make sure we continue our emphasis on a strong academic program.

''Our athletic program will enjoy a lot of momentum and we'll look forward to continued success there as well as it works to support quality academics.''