There is provided an SOI substrate having an SOI structure with an insulating layer and a surface single crystal silicon layer successively formed on a single crystal wafer, the SOI substrate having no pit generation in the SOI layer, being producible at low cost and at high productivity and having excellent gettering capacity, wherein the SOI substrate contains nitrogen and carbon with a nitrogen content of no greater than 1.times.10.sup.16 atoms/cm.sup.3 and a carbon content of no greater than 1.times.10.sup.18 atoms/cm.sup.3.