Low frequency damping in the process of plastic deformation of nickel containing various amount of carbon was measured on a small tensile testing machine. A series of internal friction peaks was observed on the internal friction-strain curve when the specimen contained a suitable amount of carbon. A study was made on the effect of heat treatment, previous cold-working, and temperature of measurement on this internal friction. It is suggested that the series of internal friction peaks is associated with the alternate anchoring of dislocations by atmospheres of solute atoms and their subsequent escaping in the course of plastic deformation.