The invention provides an indoor unit of a vertical air conditioner. The indoor unit comprises a machine shell, a heat exchanger, a first cross flow fan and a second cross flow fan; the heat exchange is arranged in the machine shell; the first cross flow fan and the second cross flow fan are arranged up and down in the machine shell, vertically extend along an axis and are arranged collinearly; the machine shell comprises a framework, a bottom plate, a front upright post, a rear upright post, a left upright post, a right upright post and a shell; the framework is used for mounting the heat exchanger, the first cross flow fan and the second cross flow fan; the bottom plate is arranged below the framework and is used for supporting the indoor unit of the vertical air conditioner; the front upright post and the rear upright post respectively extends upwards from the front and rear sides of the bottom plate to the bottom end of the framework to support the framework; the left upright post and the right upright post respectively extend upwards from the left and right sides of the bottom plate to the top end of the framework to fix the framework; and the shell surrounds the outer side of the framework, the lower end of the shell extends to the edge of the bottom plate, a plurality of air outlets are formed in the front side of the shell, and an air inlet is formed in the rear side of the shell. The indoor unit of the vertical air conditioner, provided by the invention, is relatively low in fan air pressure loss and capable of saving more energy during operation and has various air supply modes, so that the user experience is improved.