The long-term creep behavior of a Ni-based superalloy Haynes 282 at 700 and 750 degrees C was investigated. The creep curves exhibit the traditional shape with three creep stages. The coarsening of the gamma' phase during creep at 700 and 750 degrees C can be detected. The applied stress plays an important role in the coarsening of gamma' particles because of the lattice misfit and the difference of elastic modulus between the matrix and gamma' phase. Dislocation shearing into the gamma' phase and the Orowan process are the dominant creep deformation mechanisms at 700 degrees C/322 MPa. Dislocations tend to shearing into gamma' phase at first; nevertheless, the Orowan bowing mechanism replaces the process of shear as the coarsening of gamma' phase. The dominant deformation mechanism at 750 degrees C/187 MPa and 750 degrees C/215 MPa is dislocation gliding combined with dislocation climbing. Dislocation networks distributed in the interface of gamma/gamma' phase may change the direction of dislocations and promote them to climb over the gamma' phase. The fracture surfaces were observed by scanning electron microscopy. Intergranular fracture is the dominant failure mode of the three samples because of the softening of grain boundary and stress concentration. Quasi-cleavage fracture, which are attributed to the stress concentration at the carbides/matrix interface, can be observed on the fracture surface of the specimen crept at 700 degrees C/322 MPa, whereas dimples with small precipitates inside can be detected on the fracture surface of the samples crept at 750 degrees C/187 MPa and 750 degrees C/215 MPa.