PURPOSE:To conduct sure floating without being effected with flow. CONSTITUTION:The floating valve is a two position solenoid changeover valve which is connected respectively to the pair-forming cylinder passages 2, 3 of a solenoid type cylinder operation direction control valve VA and is equipped with the interception position 11 of both cylinder passages 2, 3 and a floating circuit 12 to connect both cylinder passages 2, 3 to a tank circuit Ta, and usually retention is made at the interception position 11, but by the operation of a solenoid, both cylinder passages 2, 3 are connected to each other by means of the floating circuit 12, and connected to the tank circuit Ta. Accordingly, at the time of floating operation, as both cylinder passages 2, 3 are connected to each other and are connected to the tank circuit Ta, there occurs no pressure difference between both cylinder passages 2, 3, and floating can be carried out effectively.