A microelectromechanical system includes a spacer layer, a first corrugated conductive diaphragm, and a second corrugated conductive diaphragm. The spacer layer includes counter electrode walls, slots and support walls extending along a first direction. The counter electrode walls, slots and support walls are arranged alternately in a second direction. The first corrugated conductive diaphragm includes first crests and first troughs arranged alternately in the second direction. The second corrugated conductive diaphragm includes second crests and second troughs arranged alternately in the second direction. The spacer layer is received in a cavity formed by the first and second corrugated conductive diaphragms. The support walls are respectively sandwiched between the aligned first troughs and second crests. The counter electrode walls are respectively suspended in the corresponding chambers formed between the aligned first crests and second troughs. The microelectromechanical system of the present disclosure has a high level of acoustic compliance and sensitivity.