The automobile entry detector for garages is a signaling system designed to assist a motorist with properly positioning a vehicle upon pulling into a parking structure, such as a household garage. This device could be offered in various embodiments, including as an aftermarket accessory for existing garage door openers or as an integral part of a new garage door opener design. The preferred embodiment of the device includes a garage door opener motor and controller, a garage door opener control switch, a light transmitter that transmits a beam of light to a light receptor with an LED indicator, a photocell, and an indicator lamp located on the rear wall of the garage. The LED indicator is extinguished when the beam of light is unbroken, and the photocell relays this information to activate the lamp at the same time as the LED. When the leading edge of a vehicle passes through the light beam, the LED and indicator lamp are illuminated and are only extinguished after the trailing edge of the vehicle has passed through the beam, indicating that the vehicle is properly positioned to allow unobstructed closure of the garage door.