There are provided a touch sensing device and a touchscreen device. The touch sensing device includes: a driving circuit applying a driving signal having a predetermined first period to a node capacitor; a buffer circuit converting capacitance of the node capacitor into a voltage signal; a buffer capacitor being charged and discharged depending on an output voltage from the buffer circuit; and an integration circuit integrating voltages charged in the buffer capacitor, wherein, in a normal touch mode, the buffer circuit integrates capacitance of the node capacitor to generate the voltage signal, and, in a proximity touch mode, the buffer circuit generates the voltage signal by following the voltages charged in the node capacitor.