The invention discloses a portable test tube rack. The portable test tube rack comprises a horizontal plate, the horizontal plate is provided with a plurality of through holes, and four corners of thehorizontal plate are connected with vertical support plates through connecting pieces; the vertical support plates are located at two ends of the horizontal support plate; and every connecting pieceincludes a first circular plate and a second circular plate parallel to the first circular plate, a space between the first circular plate and the second circular plate is divided into four cavities by connecting plates, two groups of rib plates are arranged at one side, far from the first circular plate, of the second circular plate, every group of the rib plates comprises two mutually parallel plate bodies, the two groups of rib plates are vertically arranged to form four slits, and the slits and the connecting plates are in the same plane. The portable test tube rack can be randomly dismounted, is portable, occupies a small area after being dismounted, and can be assembled into an up-and-down multilayer structure or a horizontal structure as needed. The portable test tube rack is extremely suitable for field mass sampling, and has great promotion values.