The jadagan (, , or Siberian harp) is a wooden board zither of the Khakas people in Siberia.
The jadagan usually has 6 or 7 strings stretched across movable bridges and tuned a fourth or fifth apart. The body is hollowed out from underneath like an upturned trough. It has a convex surface and an end bent towards the ground. The strings are plucked and the sound is very smooth. The length of the instrument is around .
The instrument was considered to be sacrosanct and playing it was a rite bound to taboos. It was mainly used at court and in monasteries, since strings symbolised the twelve levels of the palace hierarchy.
Folklorist Nancy Thym-Hochrein has researched the instrument, and musician Raphael De Cock is a contemporary player.