Microalgae are a potential source of different commercial products thanks to their metabolic products. However, the use of microalgae is hampered by high production cost, especially microalgal harvesting. Different microalgal harvesting methods have been developed in an attempt to cut down the harvesting cost. However, these methods have focused more on the quantity of microalgal biomass harvested and on lipid content. This study aimed at investigating the effect of harvesting methods on the content of microalgal lipids but also on other products such as proteins and carbohydrates. Moreover, the effects of microalgal harvesting methods on the environment were assessed using Life Cycle Analysis (LCA) approach. Natural community of microalgal biomass was harvested by four different methods, namely centrifugation, chemical flocculation, pH flocculation and Tangential flow Filtration (TFF). Flocculation methods and TFF were combined with centrifugation for further dewatering of microalgal biomass. Total lipids, proteins and carbohydrates were extracted from microalgal dried biomass and quantified. The results revealed that centrifugation and TFF do not affect microalgal products whereas chemical flocculation and pH flocculation significantly decrease microalgal lipids, proteins and carbohydrates. The least efficient harveting method  was pH flocculation which decreased TL, TP, and TC up to 47%, 67% and 50 % respectively. Microalgal products were potentially reduced due to a combination of oxidative stress and centrifugal forces. The negative effects of harvesting methods on the environment included mainly fossils depletion, climate change, human toxicity and they are associated with the electricity used during centrifugation and flocculants used.  This study gives insights into the effects of harvesting methods on the quality of the biomass and the environment. Efficient harvesting of good quality biomass is a step forward for valorisation and sustainable production of microalgal biomass.