The invention relates to a transformer substation HGIS combined electrical apparatus safe operation caution baffle bar. The baffle bar includes a horizontal rod and a vertical rod; the horizontal rod and the vertical rod are connected to form a 7-shaped structure; a caution board is arranged on the horizontal rod; and a clamping fastener for clamping a prompt area fixing rod is arranged on the bottom of the vertical rod. When a transformer substation HGIS combined electrical apparatus safe operation caution baffle bar is powered off, a case of the HGIS combined electrical apparatus can clearly define a working range, a worker can know a power-off device range and a working area, and personal, device and power grid accidents due to the fact that the worker strays to a charged interval can be effectively prevented.