The invention discloses a high-reliability separation state detection method. The method comprises the following steps that: step one, a detection circuit is arranged, a first group of compression switches 1 and 2 are connected in parallel and a second group of compression switches 3 and 4 are connected in parallel, the two groups of compression switches are connected in series, an add-drop short overline 1 and an add-drop short overline 2 are connected with the two groups of compression switches in parallel to form fourth paths of circuits, and the detection system is connected with common ends of the four paths of circuits to form a closed loop; step two, the detection system receives a separation instruction signal that indicates separation of an aircraft and an aerial carrier and is sent out by a ground control system and collects on-off information of the detection circuit; step three, the detection system receives signals from the four paths of circuits; and step four, the detection system carries out processing on the four-path signals received at the step three. According to the invention, only compression switches, compression switch fixing assemblies, separation plugs, and add-drop wires are used for state detection and the traditional separation mechanism including a gas circuit disconnection device and a fluid path disconnection device is replaced, thereby lowering the cost.