This document is an updated review on the use of probiotics to the freshwater prawn Macrobrachium sp. culture in biofloc systems, pointing out the benefits in growth, survival, improvements in the immune system, pathogen control, and water quality. The review also emphasizes some aspects that need to be defined with greater accuracy, like the effect of doses and times of probiotic administration and refers to bacterial dynamics associated with biofloc. This review aims to enhance the knowledge of probiotics in commercially important species such as the freshwater prawn.