There is no university officially called "Wisconsin University". There is the
University of Wisconsin–Madison, which is a large university, and the
University of Wisconsin System, which is a system comprising several universities including UW-Madison, UW-Milwaukee, UW-Eau Claire, and others.
To answer your question accurately, I need to know which Wisconsin university you're asking about. Each university has its own enrollment figures. You can find the enrollment numbers for each UW System university on their respective websites.