The utility model discloses a flexible, the passive protection net being convenient for installation and having warn function high with interception intensity, this passive protection net include wire rope net, fixed wire rope net the steel column, go up supporting rope, supporting rope and the pull -up anchor line and the subassembly of warning down, the steel column bottom through connecting screw rod fixed mounting on the base, go up supporting rope, down supporting rope with wire rope net and steel column fixed connection together, the pull -up anchor line is taut fixed with the top of steel column, the subassembly of warning including set up in wire rope net, go up force sensor on supporting rope or the pull -up anchor line, set up in controlling means, warning light and the bee calling organ on steel column top. The utility model discloses it is flexible high with interception intensity, adopt the modularization mounting means, shorten time limit for a project and operating expenses, the subassembly of warning is convenient for the staff and is in time discover the dangerous situation, is favorable to in time, accurately investigates and overhaul the protection network, improves the safety protection performance of protection network.