A vehicle-mounted non-contact operation detection device, comprising: a plurality of sensors (141, 142, 143, 144) each of whose output detection value is changed according to a position of a detection object in a detection range thereof; and a control section that is configured to detect non-contact operation based on a mode of the detection value of each of the plurality of sensors (141, 142, 143, 144) and acquires elapsed time when the detection value of each of the plurality of sensors (141, 142, 143, 144) reaches a peak, wherein the control section executes one of a first mode and a second mode as an operation mode, in the first mode, specifies a type of non-contact operation based on a first rule to determine whether or not the non-contact operation is an effective operation, and in the second mode, specifies the type of non-contact operation based on a second rule to determine whether or not the non-contact operation is an effective operation, and determines not to specify the type of non-contact operation when among the plurality of sensors (141, 142, 143, 144), there is at least one sensor (141, 142, 143, 144) which cannot acquire an elapsed time when the detection value reaches the peak in the first mode and the second mode, in the detection range of the sensor (141, 142, 143, 144), a detection range in which the non-contact operation is detected differs in the first mode and the second mode, and the control section detects the non-contact operation in the detection range of the operation mode which is executed. a plurality of sensors (141, 142, 143, 144) each of whose output detection value is changed according to a position of a detection object in a detection range thereof; and a control section that is configured to detect non-contact operation based on a mode of the detection value of each of the plurality of sensors (141, 142, 143, 144) and acquires elapsed time when the detection value of each of the plurality of sensors (141, 142, 143, 144) reaches a peak, wherein the control section executes one of a first mode and a second mode as an operation mode, in the first mode, specifies a type of non-contact operation based on a first rule to determine whether or not the non-contact operation is an effective operation, and in the second mode, specifies the type of non-contact operation based on a second rule to determine whether or not the non-contact operation is an effective operation, and determines not to specify the type of non-contact operation when among the plurality of sensors (141, 142, 143, 144), there is at least one sensor (141, 142, 143, 144) which cannot acquire an elapsed time when the detection value reaches the peak in the first mode and the second mode, executes one of a first mode and a second mode as an operation mode, in the first mode, specifies a type of non-contact operation based on a first rule to determine whether or not the non-contact operation is an effective operation, and in the second mode, specifies the type of non-contact operation based on a second rule to determine whether or not the non-contact operation is an effective operation, and determines not to specify the type of non-contact operation when among the plurality of sensors (141, 142, 143, 144), there is at least one sensor (141, 142, 143, 144) which cannot acquire an elapsed time when the detection value reaches the peak in the first mode and the second mode, in the detection range of the sensor (141, 142, 143, 144), a detection range in which the non-contact operation is detected differs in the first mode and the second mode, and the control section detects the non-contact operation in the detection range of the operation mode which is executed.