Against the background of the transformative renewal of legacy university campuses, this study takes three legacy campuses of Zhejiang University—Hubin, Huajiachi, and Yuquan—and their surrounding communities as empirical cases to investigate three campus transformation modes: overall replacement, partial replacement, and internal renewal. Based on space-syntax indicators, a two-dimensional “function–structure” evaluation framework for town–gown interaction space is constructed. The study quantitatively compares the transformation differences among the three modes, summarizes their spatial characteristics, and further proposes transformation strategies that align transformation objectives with appropriate renewal modes.