Recently, several strains of microalgae have been studied as they contain high lipid content capable to be converted tobiodiesel. Fresh water microalgae Chlorella vulgaris studied in this research was one of the proof as it contained hightriacyl glyceride which made it a potential candidate for biodiesel production. Factors responsible for good growing ofmicroalgae such as CO2 and nitrogen concentration were investigated. It was found that total lipid content wasincreased after exposing to media with not enough nitrogen concentration. However, under this nitrogen depletionmedia, the growth rate was very slow leading to lower lipid productivity. The productivity could be increased byincreasing CO2 concentration. The lipid content was found to be affected by drying temperature during lipid extractionof algal biomass. Drying at very low temperature under vacuum gave the best result but drying at 60oC slightlydecreased the total lipid content.