The invention discloses a material detection device and method. The device comprises a detected weight and a control device. The detected weight is hoisted above a material storage bin through traction of a steel wire rope. The control device is used for controlling the steel wire rope to be wound up and unwound so that the detected weight can move at an even speed in the vertical direction in the storage bin. The method includes the steps that the height h from the top of the storage bin to the material face is obtained by sensing the state change of the detected weight; then, the material stock W in the storage bin is calculated according to the following form: W=Pi/4*D<2> / (H-h, 0) Rho*d*h, wherein Rho=alpha1n(h)+b, wherein the Rho is a logarithm relation between the material density in the storage bin and the height h. According to the method, the weight of the material is measured through a counter weight method, an expensive level gage is omitted, so the cost is greatly lowered; meanwhile, the weight of the material is obtained through integral computation according to the logarithm relation between the material density in the storage bin and the height h , the situation that the density is different while the height of the powdery material is different is taken into account, so the correspondence between the density of the material and the corresponding height can be maintained, and measurement results are calculated accurately.