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Gasification is a thermal process of converting dry biomass feedstock into a mixture of gases that can be burnt in internal combustion engines and gas turbines. The use of producer gas to run internal combustion engine was first tried in around 1881. It was referred to as 'suction gas', because the gas was sucked by the engine from the gasifier. It was also known as ‘town gas’ or ‘coal gas’. A variation of this gas (using steam or hydrogen instead of oxygen or air) is also known as ‘synthesis gas’ because a variety of chemical compounds can be made from it. The essential chemical species in all these gases are CO (Carbon monoxide) and H2 (Hydrogen), both of which burn to release heat. Town gas was predominantly used for street lighting in early European cities like London. It lost out to natural gas because it is highly poisonous due to the presence of carbon monoxide. Gradually the use of producer gas as a domestic fuel was taken over by cheaply available natural gas. The advent of petroleum further accelerated a decline in the need for producer gas. Gasification is the generic term to describe the technology of conversion of solid fuels into gaseous ones. Thus there can be coal gasification or biomass gasification. Although both coal and biomass can be burnt directly to get heat energy, gasification of these fuels has certain advantages which cannot be achieved by direct burning. The main advantage of biomass gasification is that the resultant gaseous fuel can be used in an engine directly. Since gas engines are readily available, through biomass gasification one can produce electricity. It is certainly possible to get electricity from directly burning biomass, but that would require, first, a boiler for making steam and then a steam turbine. Environmentally, Biomass Gasification is a clean technology free of CO2 emissions, if well designed. Utilization of renewable energy sources makes it a sustainable energy system. Biomass Gasification has been receiving attention because of the following reasons: • Reduction of wood consumption up to 50% • Environmentally sound technology • Decentralized electricity generation • Good use of domestic resources • Savings in foreign currency in importing energy • Boost to agriculture • Easy to operate and maintain • Local employment • Replacing the fossil fuels. The disadvantages can successfully be mitigated both by "good practices" and engineering measures. In developed countries, there is not much interest in small-scale decentralized electricity generation because of its high cost. However, co-firing, i.e. using biomass along with other fuels to reduce fossil fuel consumption is becoming very popular and this practice is responsible for the consumption of vast quantity of biomass. Developed countries like Brazil are more interested in liquid bio-fuels, bio-ethanol and bio-diesel. India is becoming a leading user of the smallscale version of this technology and many new designs are being innovated. Thailand is also experimenting with it. Bangladesh is an agrarian country and there is easy availability of agriculture-based mass, which can be used to generate energy. Burning this biomass directly is the oldest and also the least efficient method of generating energy. On the other hand, gasification of this mass is technologically viable and at the same time has the potential to replace the consumption of fossil fuel to some extent. In this study, the goal is to construct a downdraft biomass gasifier at laboratory scale and to check whether the required composition of producer gas can be achieved successfully. The construction of the gasifier is based on the design proposed by Bhattacharya et al..