A method for producing a hybrid substrate comprising the steps of: furnishing an SOI substrate which is obtained by stacking a first silicon oxide layer and a silicon active layer in that order on a silicon substrate such that a terrace portion not having the silicon active layer is left at an outer peripheral portion of the silicon substrate surface, forming a second silicon oxide layer on the silicon active layer surface of the SOI substrate, prior to bonding the SOI substrate to a support substrate having a different coefficient of thermal expansion from the SOI substrate, subjecting the surface of the SOI substrate and/or the support substrate to be bonded to activation treatment, bonding the SOI substrate to the support substrate at a temperature in the range from 100°C to less than 250°C, with the second silicon oxide layer interposed therebetween, to form a bonded substrate in which, at said peripheral terrace portion of the SOI substrate where the silicon active layer is absent, the SOI substrate and the support substrate do not contact one another, subjecting the bonded substrate to a repeated combination of a consolidation heat treatment for increasing the bond strength between the SOI substrate and the support substrate and a grinding/thinning treatment of thinning the silicon substrate by grinding, the combination being carried out at least twice and under the conditions that - the temperature of the first consolidation heat treatment is equal to or higher than the bonding temperature, - the silicon substrate after the first grinding/thinning treatment has a thickness of 130 μm at the thinnest, - the temperature of the final consolidation heat treatment is from 200°C to less than 250°C, and - the silicon substrate after the final grinding/ thinning treatment has a thickness of 60 μm at the thinnest, etching away the thinned silicon substrate until the first silicon oxide layer is exposed, and etching away the exposed first silicon oxide film, yielding a hybrid substrate in which the silicon active layer is disposed on the support substrate via the silicon oxide layer. furnishing an SOI substrate which is obtained by stacking a first silicon oxide layer and a silicon active layer in that order on a silicon substrate such that a terrace portion not having the silicon active layer is left at an outer peripheral portion of the silicon substrate surface, forming a second silicon oxide layer on the silicon active layer surface of the SOI substrate, prior to bonding the SOI substrate to a support substrate having a different coefficient of thermal expansion from the SOI substrate, subjecting the surface of the SOI substrate and/or the support substrate to be bonded to activation treatment, bonding the SOI substrate to the support substrate at a temperature in the range from 100°C to less than 250°C, with the second silicon oxide layer interposed therebetween, to form a bonded substrate in which, at said peripheral terrace portion of the SOI substrate where the silicon active layer is absent, the SOI substrate and the support substrate do not contact one another, subjecting the bonded substrate to a repeated combination of a consolidation heat treatment for increasing the bond strength between the SOI substrate and the support substrate and a grinding/thinning treatment of thinning the silicon substrate by grinding, the combination being carried out at least twice and under the conditions that - the temperature of the first consolidation heat treatment is equal to or higher than the bonding temperature, - the silicon substrate after the first grinding/thinning treatment has a thickness of 130 μm at the thinnest, - the temperature of the final consolidation heat treatment is from 200°C to less than 250°C, and - the silicon substrate after the final grinding/ thinning treatment has a thickness of 60 μm at the thinnest, - the temperature of the first consolidation heat treatment is equal to or higher than the bonding temperature, - the silicon substrate after the first grinding/thinning treatment has a thickness of 130 μm at the thinnest, - the temperature of the final consolidation heat treatment is from 200°C to less than 250°C, and - the silicon substrate after the final grinding/ thinning treatment has a thickness of 60 μm at the thinnest, etching away the thinned silicon substrate until the first silicon oxide layer is exposed, and etching away the exposed first silicon oxide film, yielding a hybrid substrate in which the silicon active layer is disposed on the support substrate via the silicon oxide layer.