A transmissive sampling module used to fix a test object to allow a spectrometer body to obtain optical information of the test object and includes a bearing base, a light emitting element, an adapter element and a sample accommodating device. The bearing base includes a first accommodating tank body. The light emitting element is disposed in the bearing base and used to emit an illumination beam. The adapter element is disposed in the first accommodating tank body and further includes a body portion and an abutting rib extending from the body portion. The body portion and the abutting rib jointly form a second accommodating tank body. The sample accommodating device at least partially surface-contacts with a second tank surface through a second light exit. A spectrometer having the transmissive sampling module is provided.