A milking apparatus for laboratory animals enables a milking operation to be performed on a laboratory animal (such as a rat) by a single experimenter, and also enables universal milking data to be obtained that is not influenced by individual difference among experimenters. A teat cup enables milking to be performed directly from the nipple of a relatively small and prolific laboratory animal such as a rat and mouse. The invention provides useful means for clarifying the influence of harmful extrinsic substances on living organisms via milk. The apparatus comprises a milk-collecting container 10 whose inside can be kept blocked from the outside air, two, i.e., a first and second, tubes 12, 13 inserted into the milk-collecting container in a communicated manner, and a teat cup 20 replaceably mounted on the other end of the first tube 12. The other end of the second tube 13 is provided with a pressure switching means such as electromagnetic valves 33A and 33B that can switch the state inside the second tube 13 between a state where the inside is connected to the negative pressure creating source 35 and another state where it is opened to the atmosphere.
