NOVELTY - An electrolysis and concentration device has a condensation pipe (13) arranged in a cooling device (9). Positive and negative electrodes of a solid polymer electrolyte (SPE) tank (4) are connected with an anode and a cathode of a power supply. Oxygen and hydrogen outlets of a SPE cell are connected with the pipe. Oxygen and hydrogen exhaust pipes are designed as feeding ports (2). A laser transmitter and a laser receiver (16) are located at sides of a vertical pipeline part of two branched pipelines. The laser receiver outputs a liquid level signal to a control circuit (8).    USE - Electrolysis and concentration device for tritium in water.    ADVANTAGE - The device has high stability, reliability and high working efficiency.    DETAILED DESCRIPTION - An electrolysis and concentration device has a reflowing condensation pipe (13) arranged from top to bottom in a cooling device (9). Positive and negative electrodes of a solid polymer electrolyte (SPE) tank (4) are connected with an anode and a cathode of a direct current regulated power supply. Oxygen and hydrogen outlets of a SPE cell are respectively connected with the reflowing condensation pipe through an oxygen sample bottle (14) and a hydrogen sample bottle (18) and separately connected to outside the cooling device through oxygen and hydrogen exhaust pipes. The oxygen and hydrogen exhaust pipes are designed as feeding ports (2), and the outlets are connected with the feeding ports through two branched pipelines. A laser transmitter and a laser receiver (16) are oppositely located at sides of a vertical pipeline part of the branched pipelines. The vertical pipeline part between the laser transmitter and the laser receiver is transparently formed, where the laser receiver outputs a liquid level signal to a control circuit (8).    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic sectional view of an electrolysis and concentration device.    Feeding ports (2)    SPE tank (4)    Control circuit (8)    Cooling device (9)    Reflowing condensation pipe (13)    Oxygen sample bottle (14)    Laser receiver (16)    Hydrogen sample bottle (18)