Students and parents at West Nottinghamshire college are being consulted over the plans.
Despite being voluntary, college bosses believe the tests, which they would start in September, would help raise awareness of the dangers of substance abuse.
Kevan Hodgson, head of customer services at the college, described the move as an extension to health initiatives, such as a health food shop and free contraception, which have been available at the college for years.
He said: "We are trying to alert young people partly to the problems it would cause them at college and to help them behave in a more socially acceptable way.
"I don't think any college could say they haven't had these problems. We are trying to be realistic about it, but it is rare."
The college has around 2,500 students each year. Two were excluded because of drugs in 2004-5, but none has been excluded so far this year. Offences punishable by exclusion include being under the influence of drugs, taking drugs or distributing them while at college.
One idea being explored is a type of fabric that can be wiped across the forehead and can detect illegal substances in the bloodstream.
Mr Hodgson added: "There are also machines that can detect it in the atmosphere so you can tell if drugs were being exuded through sweat or breath and that would give reason for us taking it further." A positive test would not automatically mean police involvement.
He said: "While refusal to participate wouldn't be an indication of anything - there would be peer pressure from people to take part."
He said initial responses were positive.
Support staff rather than lecturers would carry out the tests.
Ellie Russell, the National Union of Student's vice president for FE, said:
"College campuses should be drug-free environments. However, we do not believe that random drug-testing is necessarily the best way to ensure that.
"We believe that it is more important to build up a genuine consensus. All policies which infringe on the civil rights of students should be created in consultation with the students themselves."
Libby Purves, TES backpage