The invention discloses a hydraulic transmission control unit of a self-elevating-type marine platform pile leg, and the unit comprises three parts, namely a hydraulic transmission module, a hydraulic control module and an electric control module, wherein the hydraulic transmission module consists of a base, a pile leg and four hydraulic transmission assemblies; each hydraulic transmission assembly consists of an internally-arranged ultrasonic route sensing hydraulic oil cylinder, a common hydraulic oil cylinder, an upper pin, a lower pin, a slide block and a plug device; each plug device consists of a bracket, a plug oil cylinder and a plug; the hydraulic control module consists of a hydraulic oil tank, a hydraulic pipeline, an air filter, a motor, a hydraulic pump, a check valve, an overflowing valve, four hydraulic transmission control assemblies and four hydraulic plug control assemblies; each hydraulic transmission control assembly in the hydraulic control module consists of an electromagnetic pressure adjusting valve, an electromagnetic speed regulating valve, a three-position four-way electromagnetic steering valve and a pressure sensor; and each hydraulic plug control assembly consists of the electromagnetic pressure adjusting valve and the three-position four-way electromagnetic steering valve. The hydraulic transmission control unit of the self-elevating-type marine platform pile leg disclosed by the invention has the advantages that the debugging is simple, the pressure sensor does not need to be arranged on a pile shoe, and the influences of seawater on the service life of the sensor are avoided.