This paper investigates the determinants of startup survival within university-based innovation ecosystems in a developing-country context. It focuses on the University of Birjand (Iran) to measure the survival rate of startups and identify the key individual, organizational, and institutional factors influencing their longevity. Using event history analysis, data were collected from 124 startups operating at the University of Birjand’s Innovation and Entrepreneurship Center between 2019 and 2024. The survival rate was estimated using the life-table method, and the Cox proportional hazards model examined the effects of multiple variables on venture survival. The results indicate that founder education, team size, company registration status, loan acquisition, and business consultation significantly enhance startup survival, whereas location within the University of Birjand’s Innovation and Entrepreneurship Center and strict internal regulations increase the risk of exit. Gender, age, affiliation with the university, local origin, and equipment support show no significant effects. Among all variables, loan acquisition and internal regulations exhibit the strongest effects in opposite directions: receiving loans reduces the hazard of exit by approximately 82%, whereas stricter internal regulations increase it by about 166%.