The fixed bed slow pyrolysis of lemongrass (Cymbopogon flexuosus) is studied with the aim of determining the main characteristics of the bio-oil formed and the quantity of bio-oil produced. Variables investigated were temperatures between 350 and 550 degrees C, particle sizes between 0.3-0.6 and 1.0-1.25 mm, and heating rate of 15 and 45 degrees C/min. Under the conditions of this study, temperature was very significant parameter to determine the product yield. Whereas particle size and heating rate have less effect on the yield. Higher pyrolysis temperature resulted in higher fixed carbon content. At higher pyrolysis temperature, more volatiles have been removed, which resulted in lower char yield. The maximum bio-oil yield of 40.6 wt% was obtained at the final pyrolysis temperature of 450 degrees C, particle size range of 0.71-1.0 mm, and heating rate of 45 degrees C/min in a fixed-bed lab-scale reactor. Chromatographic studies on the bio-oil showed that the oil obtained from lemongrass can be used as a renewable fuel having heating value of 17.2 MJ/kg and chemical feedstock.