Aiming at efficient path planning of the gas insulated switchgear (GIS) robot which is used for inspecting and maintaining the GIS equipment, this paper proposed a Beetle Antennae Search (BAS)-inspired RRT* algorithm. The new algorithm combines basic RRT* with BAS, a metaheuristic approach, to inspire the sampling, and utilizes a weighted lazy extension mechanism to contribute expanding useful nodes. BASL-RRT* is firstly compared with three improved RRT* algorithms and simulation results verify the effectiveness and the superiority of BASL-RRT*. Then, we apply this new method on path planning of GIS robot. The result shows that safe and smooth path could be obtained efficiently.