The utility model relates to the field of laboratory equipment, in particular to a precise and adjustable regenerant spraying device for a laboratory. The utility model provides the precisely adjustable regenerant spraying device for the laboratory, which is capable of quantitatively spraying a regenerant, simple in structure, convenient for precisely controlling the dosage to adapt to different spraying requirements, capable of improving the detection efficiency and accuracy and reducing the maintenance cost, and convenient to use. A precise and adjustable regenerant spraying device for a laboratory comprises a device body, a threaded head and the like, and the threaded head is connected to the left side of the upper portion of the device body. The limiting ring is moved to the position corresponding to the scales, then the screw is rotated for fixation, the connecting shaft is pushed to move, the stopping block makes contact with the limiting ring, then the corresponding amount of regenerant is pushed out to achieve quantitative spraying, quantitative spraying can be conducted on the regenerant, the structure is simple, and operation is convenient. The dosage can be accurately controlled to meet different spraying requirements, the detection efficiency and accuracy are improved, the maintenance cost is reduced, and use is convenient.