The condition of vehicle very crowded traffic, that condition caused by high intensity and overload amount vehicle. Usually to get amount of vehicle in street still use manual counting, Ā use some people to count every vehicle that through the ways, every counting process divide by certain time. Ā the Automatics of vehicle counting use laser and photodiode sensors as data input that can be possessed by Microcontrollers AT89S51 and data was sent to basis data through serial communication to PC. This application cant apply manual counting because PC has shown by display, helped by Visual Basic. Ā Design can detect laser until range 7 meters and ASCII 1 that transmitted microcontroller to PC can be read, saved and shown by DzulAT89S51Vb. The result of test, the amount of vehicle can be detected, 66 four-wheel vehicles with range from 16: 33 until 18: 33, time divides by 10 minutes. The accurate of devices reach 95, 45%, with mean 97,083%.