ONUSS stands for Organization of Nairobi University Science Students. It draws its membership from the students in the College of Biological and Physical Sciences based in Chiromo Campus of the University of Nairobi. The organization started to look into the welfare of science students has been instrumental in performing various activities in and out of the campus.

An array of past activities includes.

• Chiromo Sports Day.
• Health and safety Awareness Day.
• Jijue Day-A HIV/AID
• mr and miss chiromo