A method for diagnosing a turnout fault, comprising: (S110) 8110; acquiring a target turnout action curve of a target turnout; the turnout action curve comprising a series of discrete sequence items generated by turnout actions at different trigger times; (S120) segmenting the target turnout action curve into curve segments, according to values of the discrete sequence items in the target turnout action curve; and (S130) according to the segmented result of the target turnout action curve, performing fault diagnosis on the curve segment in each turnout action phase, so as to implement the fault diagnosis for the target turnout, including at a turnout unlocking phase and a turnout switch phase, if values of the discrete sequence items in curve segments at the turnout unlocking phase and the turnout switch phase in the target turnout action curve are continuously greater than a turnout unlocking threshold value for a preset time period, determining that the target turnout has a turnout unlocked fault; at a turnout switch phase, if values of the discrete sequence items in curve segments at the turnout switch phase in the target turnout action curve are continuously less than a turnout idling threshold value for a preset period of time, determining that the target turnout has a turnout idling fault; at a turnout switch phase, if the target turnout action curve is greater than a turnout jam threshold value, determining that the target turnout has a turnout jam fault; at a turnout lock phase, if values of the discrete sequence items in curve segments at the turnout locking phase of the target turnout action curve are all greater than zero, determining that the target turnout has a turnout unlocking fault. (S110) 8110; acquiring a target turnout action curve of a target turnout; the turnout action curve comprising a series of discrete sequence items generated by turnout actions at different trigger times; (S120) segmenting the target turnout action curve into curve segments, according to values of the discrete sequence items in the target turnout action curve; and (S130) according to the segmented result of the target turnout action curve, performing fault diagnosis on the curve segment in each turnout action phase, so as to implement the fault diagnosis for the target turnout, including at a turnout unlocking phase and a turnout switch phase, if values of the discrete sequence items in curve segments at the turnout unlocking phase and the turnout switch phase in the target turnout action curve are continuously greater than a turnout unlocking threshold value for a preset time period, determining that the target turnout has a turnout unlocked fault; at a turnout switch phase, if values of the discrete sequence items in curve segments at the turnout switch phase in the target turnout action curve are continuously less than a turnout idling threshold value for a preset period of time, determining that the target turnout has a turnout idling fault; at a turnout switch phase, if the target turnout action curve is greater than a turnout jam threshold value, determining that the target turnout has a turnout jam fault; at a turnout lock phase, if values of the discrete sequence items in curve segments at the turnout locking phase of the target turnout action curve are all greater than zero, determining that the target turnout has a turnout unlocking fault. <EOS>