The utility model relates to a liquid capsule type soil stress test device, send the converter including bag formula stress casing, protection tube and change: the intussuseption of bag formula stress casing is filled with the stress transfer medium, and the transmission medium is the liquid medium, and bag formula stress casing is convex with the contact surface of the soil body, it directly generates the stress signal to become the stress that send the converter will transmit the medium transmission to the output of passing signal cable becomes and send converter and bag formula stress housing seal to be connected, the outside of sending the converter in the change is installed to the protection tube, and the end is opening and draw the signal cable respectively, and another end is connected with bag formula stress housing seal. The utility model discloses an advantage embodies: can realize the contact with soil body omnirange to abundant perception unit soil stress situation of change, can change the shape along with soil deformation, have great soil deformation adaptability. Can accurate test variation of stresses state.