An outdoor unit of an air conditioner, comprising: a casing; and an electric control assembly being disposed in the casing; wherein the outdoor unit comprises a main control board and a filter board arranged side by side in a horizontal direction, and the electric control assembly comprises: a wire mounting plate sheet metal located below the main control board and the filter board and provided with a power line terminal block; and an electric control board disposed on the wire mounting plate sheet metal and provided with a wiring socket and a signal line terminal block, wherein the wiring socket, the signal line terminal block, and the power line terminal block are arranged sequentially in a direction from the main control board to the filter board; wherein the the outdoor unit further comprising a middle partition plate disposed in the casing, and configured to partition an interior of the casing into a first chamber and a second chamber, a fan wheel being provided in the first chamber, characterized in that the electric control assembly comprises a wiring component and an electric control component, the wiring component comprises the wire mounting plate sheet metal and the electric control board, the wiring component is vertically arranged in the second chamber and located below the electric control component, and a wire body on the electric control component is connected to the wiring component; and an electrically controlled welding member disposed on the top of the middle partition plate, the electric control component being inverted in the electrically controlled welding member and configured to span the first chamber and the second chamber. a casing; and an electric control assembly being disposed in the casing; wherein the outdoor unit comprises a main control board and a filter board arranged side by side in a horizontal direction, and the electric control assembly comprises: a wire mounting plate sheet metal located below the main control board and the filter board and provided with a power line terminal block; and an electric control board disposed on the wire mounting plate sheet metal and provided with a wiring socket and a signal line terminal block, wherein the wiring socket, the signal line terminal block, and the power line terminal block are arranged sequentially in a direction from the main control board to the filter board; a wire mounting plate sheet metal located below the main control board and the filter board and provided with a power line terminal block; and an electric control board disposed on the wire mounting plate sheet metal and provided with a wiring socket and a signal line terminal block, wherein the wiring socket, the signal line terminal block, and the power line terminal block are arranged sequentially in a direction from the main control board to the filter board; wherein the the outdoor unit further comprising a middle partition plate disposed in the casing, and configured to partition an interior of the casing into a first chamber and a second chamber, a fan wheel being provided in the first chamber, characterized in that the electric control assembly comprises a wiring component and an electric control component, the wiring component comprises the wire mounting plate sheet metal and the electric control board, the wiring component is vertically arranged in the second chamber and located below the electric control component, and a wire body on the electric control component is connected to the wiring component; and an electrically controlled welding member disposed on the top of the middle partition plate, the electric control component being inverted in the electrically controlled welding member and configured to span the first chamber and the second chamber.