Oxide semiconductors are highly attractive for fabrication of large-area thin-film electronics because of their high electrical performance, low process temperature, high uniformity, and ease of industrial manufacturing. N-type oxide semiconductors, such as InGaZnO, are highly developed and have already been commercialized for backplane drivers of flat-panel displays. To date, developing complementary metal-oxidesemiconductor (CMOS) technology is still an urgent issue in order to build low-power electronic circuits based on oxide semiconductors. In this work, various CMOS circuits, including inverters, NAND, NOR, XOR, d latches, full adders, and 7-, 11-, 21-, and 51-stage ring oscillators, are fabricated based on sputtered p-type tin monoxide (SnO) and n-type InGaZnO. The inverters show rail-to-rail output voltage behavior, low average static power consumption of 8.84 nW, high noise margin level up to ~40% supply voltage, and high uniformity with negligible standard deviation. The NAND, NOR, XOR, d latches, and full adders show desirably ideal input-output characteristics. The performances of ring oscillators indicate small stage delay of ~1 μs, extremely high uniformity and high yield which are essential for large-area thin-film electronics. This work may inspire constructions of low-power, large-area, large-scale, and highperformance transparent/flexible CMOS circuits fully based on oxide semiconductors for applications beyond flat-panel displays.