Liquefied Petroleum Gas (LPG) is a main source of fuel especially in urban areas because it is clean compared to firewood and charcoal. There is always a danger of the gas leakage as a result of negligence or failure on the regulating valve on the gas cylinder which pose a great danger due to highly flammable nature of the gas. Cases of gas related fire has been on the rise and this can be avoided using a gas leakage detection system and thus the need for development of a microcontroller based cooking gas detector. The use of microcontroller enables development of a high accurate and fast response detection system. The detector incorporate MQ-6 sensor (with gas detection range of 300-10000ppm) as the LPG gas sensor, PIC16F690 microcontroller as the control unit, LCD for displaying gas concentration, a buzzer as an alarm and a number of LEDs to indicate the gas leakage status. The microcontroller senses the presence of a gas when the voltages signal from the MQ-6 sensor goes beyond a certain level and gives an audiovisual alarm. The microcontroller is programmed using PIC assembly language and all the peripherals connected to it through it pins. When the system is powered on the microcontroller lit a green LED to show the absence of a gas leakage. LPG gas is released and the sensor voltage signal monitored using a digital multimeter. Below 2.0V, the green LED is kept lit and when the voltage is more or equal to 2.0V, the microcontroller blinks a red LED and set off an alarm to show the presence of a gas. The detector has a button with which the alarm can be acknowledged. The sensor as a high resistance in clean air. In the presence of LPG gas, the sensor conductivity increases and the characteristic of the sensor is that at 2.0V output from the sensor, the gas concentration is 300ppm, thus the trigger level is 2.0V. Therefore, the microcontroller based gas leakage detector based on PIC16F690 microcontroller and MQ-6 sensor is able to detect gas leakage concentration from 300ppm and give an audiovisual signal.