The static, ambient and dynamic field tests and observations of the long span Nissibi cable-stayed bridge are given in this paper. For this purpose, the ambient vibration tests, static and dynamic loading tests for different truck positions and observational investigations were implemented between May 16-19, 2015. The mobile dynamic measurement system, geodetic measurement system and bridge fixed monitoring system have been used during these tests. The experimental frequencies and mode shapes of the bridge are obtained using the ambient vibration tests with the Enhanced Frequency Domain Decomposition (EFDD) tehcnique. The static displacements of the deck and towers were determined using geodetic instruments for five different fixed truck positions on the bridge deck. The dynamic measurements were taken from the deck, pylons and cables by using the bridge fixed monitoring and the mobile measurement systems for fifteen dynamic load (DL) cases including the passage of trucks throughout the deck. Before, during and after the measurement, observational inspections on the foundations, bearings, joints, deck, cables and pylons have also been realized. The results obtained from the ambient vibration, static and dynamic loading tests are compared with the analytical results of the bridge.