There are 35 modes of guqin, which are tuned according to the pentatonic scale, and the positive tuning range has four octaves and one major second.

Among the stringed instruments, the guqin is a relatively unique musical instrument with a fretboard on the surface and no columns and frets. When playing, place the qin horizontally on the table, throw the strings with the right hand, and press the strings with the left hand to pick up the tone, completely relying on the marks of the qin logo (not limited to the 13 emblems, many of the tones are between the emblem and emblem), intonation The requirements are extremely strict.

The pitch of the open strings is not fixed and depends on the music being played. When the string is in positive tuning, the lowest open string tone of the string is the C tone of the big character group, and the tuning is arranged in order from the first string to the seventh string in a pentatonic scale, which are C, D, E, G, A, c, and d respectively. Guqin has a wide range, from C-d3, with a total of four octaves and one major second.

Guqin is also commonly used in tight five-string, slow three-string, tight five-slow and other modes.

The expressive power of the guqin is particularly rich and mellow. Using different playing techniques, it can bring out many characteristics of artistic expression. Its scattered sound (empty string sound) is bright and thick, like a bronze bell; its overtones are transparent like beads and colorful. Regions vary. The treble area is light and crisp, like a bell in the wind; the midrange area is bright and sonorous, like hitting a jade chime. According to the sound, the pronunciation is firm, also called "real sound", and the timbre of each sound area is also different. According to the various glissandos in the sound, it is soft like a song, and it also has profound and detailed expressiveness.