Microalgae are one of the most promising sustainable energy sources for biodiesel production. However, the high costs of the downstream process are a major bottleneck for commercial-scale production of biodiesel from a microalgal biomass. A novel approach called the cationic surfactant-based harvesting and cell disruption (CSHD) method was studied to determine its effectiveness in simultaneous microalgal biomass harvesting and cell disruption. Using CSHD, the harvesting efficiency reached more than 91% in less than 5 min and 97% in 90 min. Moreover, CSHD exhibited a powerful ability to disrupt the cells; the lipid recovery was increased 133% compared to not using CSHD. CSHD allowed the extraction of up to 100% of the total lipids from a wet microalgal biomass with 80% water content. All of these results were achieved without using energy-intensive equipment. Altogether, our results suggest that CSHD is an energy-efficient technique for the downstream process of microalgal lipid production.