Biomass of microalgae continues under study as promising candidate for novel biofuels and bioproducts, however, microalgae-based processes faces technical bottlenecks related to efficiency of metabolite extraction and transformation. This paper shows the development and evaluation of thermal and chemical cell disruption methods for the extraction of oil from Nannochloropsis sp. as feedstock for the production of third generation biofuels and high value fatty acids, in order to achieve lipid extraction efficiency. The thermal cell disruption process chosen was autoclave, during operation times of 1 and 3 hours at 394.15 K and 103410 Pa. Chemical treatment was based on acid hydrolysis with HCl in concentrations of 0.1, 0.5, 1 and 3 mol L-1. Organosolv Pretreatment was also used with a reaction time of 4.1 hours at 394.15 K and 103410 Pa. Results showed that the thermal and Organosolv cell disruption process increases extraction yields for biomass without pretreatment, but these did not exceed any of the results obtained with acid hydrolysis. Solution 0.5 mol L-1 HCl proved to be the most suitable for cell disruption process. In addition it was determined that the water content in the pretreated biomass, decreases the efficiency of the extraction processes.