Moisture distribution in whole yam tuber and the effect of heat-moisture treatment on the physical characteristics and drying rate of yam pieces were investigated The sampling scheme showed that the moisture was uniform throughout each slice; however the values for slices in the tail end were 18% more than those in the head end. Heat-moisture treated samples had significantly different density shrinkage, drying rate and diffusion coefficients from the untreated sample. However the observed effects were found to depend on the mode and temperature of the heat treatment. Heat treated yam pieces have greater densities than the untreated samples. Shrinkage was more when the yam was pre-heated in a sealed container (conduction heating) than samples heated in contact with water.