The utility model discloses a cable layer of 110kV transformer substation water level alarm device, including casing and head rod, the up end of casing is provided with alarm device, the inner chamber top of casing is provided with the battery, the inner chamber left side of casing is provided with first terminal, be provided with an elastic conducting strip on the first terminal, the inner chamber right side of casing is provided with the second terminal, be provided with the 2nd elastic conducting strip on the second terminal, an elastic conducting strip lies in the 2nd elastic conducting strip's top, the head rod is located the inner chamber of casing, the bottom of head rod articulates there is the second connecting rod, the bottom face of casing is provided with the pillar, the right -hand member fixedly connected with floater of second connecting rod, the battery in proper order with first terminal, second terminal and alarm device electric connection, this has been realized need not manual operation and has monitored transformer substation's cable layer water level in real time, high durability and convenient use, and have higher availability factor and monitoring rate of accuracy.