We aimed to investigate Tehran's University of Medical Sciences (TUMS) affiliated hospitals organizational readiness toward implementing the 'Autonomous Hospitals' program as a change initiative from a managerial perspective in 2020. A census covering all eligible managers working in TUMS affiliated hospitals, Tehran, Iran (350 individuals) was carried out. Overall, 281 questionnaires were returned (a 30% non-responsiveness rate). A standard construct was adopted for data collection which was validated through a process of translation- back translation, face validity, and content validity (CVI=0.86, CVR=0.76). The reliability was acquired using Cronbach's alpha coefficient (0.87 and over 0.7). Both descriptive and inferential statistics were employed to draw conclusions .SPSS 26 was used for data analysis. Total organizational readiness for change (TORC) in hospitals was 60.75%±10.11 showing a state of medium to upper-medium readiness status. Also, the 'Clear mandate and centralized leadership' theme scored the lowest mean (53.02%±15.78) for ORC. 'Hospital accreditation level' (r=-0.14, P≤0.05), 'bed occupancy rate' (r=-0.19, P ≤0.05), and 'leadership status' (r=0.26, P≤0.001), also showed significant association with TORC. In addition, 'standardized bed occuPancy rate' (P≤0.05, B=-2.41), a 'male' leader (P ≤0.05, B=3.42), and 'academic affiliation' (P≤0. 1, B=-9.52), were good Predictors of TORC based on 'Backward Multiple Linear Regression' analysis. Full support from hospital and headquarters executives, delegation of sufficient decision-making authority to hospital managers, and implementation of comprehensive performance evaluation criteria were prerequisites for robust hospital autonomy in TUMS-affiliated hospitals.