Effects of five levels of substitution (0, 30, 50, 70, 100 %) of wheat starch or corn starch for wheat flour on the properties of the sponge cakes and batters were investigated. The results were as follows : 1) Increase in starch ratio caused the decrease of batter viscosity and the increase of cake layer expansion during baking. While, replacement to corn starch induced greater shrinkage after maximum expansion according to increase of starch ratio, and consequently, there were no differences in their cake volume (cm³/g). 2) Deformation including brittleness and recovery from deformation of cake layers by repeated compressing test increased as the increase of starch ratio. Tendency appeared more clearly for corn starch-substituted cakes. 3) Differential Scanning Calorimetry (DSC) data showed that the transition peak of cake batters containing 100 % flour or starches appeared at the 30°C higher position than those of flour or starches measured with enough water. 4) The DSC data for batters substituting 30 to 70% corn starch showed two transition peaks at about 90 and 100°C corresponding to gelatinization peaks of wheat starch and corn starch, respectively. 5) Existence of ungelatinized starch in defatted 50 %, 70 % and 100 % corn starch-substituted cakes was showed by small transition peaks at about 80°C in the DSC thermogram of each sample. These data indicated that shrinkage during baking and brittleness of cake layer for the corn starch substituted cakes caused by insufficient gelatinization of corn starch in the layers.