The zheng's soundbox is constructed of wood, red sandal for its sides and bottom and wutong wood (firmiana platanifolia) for the arched soundboard, According to the historical texts, it was described as having 12 strings before the Han and Jin period (206-BC-AD 420). In succeeding periods the number of strings kept increasing; 13 after the Tang and Song (618-1279), 15 or 16 since the Ming and Qing (1368-1911), 21 since the 1960's, and 24 or 26 at present, Each string is suspended over the upper sound board by a single adjustable bridge as a device for fine tuning, The strings are tuned to give three complete octaves of a pentatonic scale, sometimes of a heptatonic one.

The instrument is rich in playing techniques. The performer plucks the strings with his right-hand fingernails (either real or simulated), while his left-hand fingers apply pressure to the strings to execute vibratos, glissando, other embellishments and occasional plucking techniques,. Sounding melodious and elegant, it is as important solo instrument now, and often in accompaniments as well.