The effect of grain size as well as creep temperature on the primary and secondary creep parameters of Sn-3 wt.% Bi alloy has been studied. It was found that the creep parameters alpha, beta, and epsilon'(s) were decreased with increasing grain size. This was explained in view of the dislocation interaction with the defects and different inclusions in the matrix. For both the primary and secondary creep, the activation energies estimated indicate that the rate-controlling mechanism is the grain boundary-sliding mechanism.