The invention discloses an automatic sample introduction device. The automatic sample introduction device comprises at least one sample introduction unit, wherein the sample introduction unit is sealed by a cover plate layer and a microfluid layer, the surface of the cover plate layer has hydrophilic property, at least two through holes are arranged on the cover plate layer, a hollowed hybridization reaction cavity and at least two hollowed microfluid channels are arranged on the microfluid layer, one end of each microfluid channel is communicated with the hybridization reaction cavity, and the other end of each microfluid channel is communicated with one through hole of the cover plate layer. Based on the hydrophilic property of the cover plate layer and under the driving of the liquid surface tension, the automatic sample introduction device enables solution to automatically enter and fully fill the hybridization reaction cavity and the microfluid channels; the flowing uniformity of the sample solution of the microarray chip can be realized on the basis of the structural design of the hybridization reaction cavity and the microfluid cavity. The automatic sample introduction device has the advantages of simplicity in preparation, and convenience in operation, high hybridization efficiency, less sample consumption, capability of automatically and quantitively introducing samples, and the like.