A non-destructive flying insect detector is disclosed. The detector creates a sheet or curtain of light comprising a sensing zone and detects, by means of light extinction, individual flying insects that intersect the sensing zone. The sensing zone is created by a beam of light that enters the sensing zone area and is then bounced between opposing reflective surfaces. Preferably a laser is utilized to generate the beam of light. The beam of light leaves the sensing zone area and is incident on a light detection device (such as a photo cell) connected to an amplifier circuit. The light detection device monitors the light intensity and is arranged and configured to detect changes in the light intensity. The changes are electronically converted to a pest detection signal and/or to a flying insect count. Each flying pest detection signal may also be associated with other monitored data. For example, the time and date when the count occurred, the temperature, and the ambient light, among other parameters may be stored with the flying insect count(s). The stored data may be transmitted in real time, transmitted periodically, and/or collected with a PDA device or the like. The detector may be completely passive or it may provide an attractant for the flying insects--such as UV lamps. Further, the detector can act as a counter alone (e.g., as a flying insect monitor without a physical trap) or it can operate together with a trap. In the latter case, the flying insect may become entangled on a glue or sticky board lying beneath the light curtain and/or become eliminated by an electrical discharge device.