Shrimp is a highly popular seafood product, valued for its nutritional richness and delicacy. The global demand for shrimp has driven the development of advanced farming systems to boost productivity and mitigate disease-related losses, significantly contributing to the aquaculture industry and economic growth in many countries. Despite these advancements, maintaining shrimp quality during postharvest handling remains challenging due to rapid quality decline caused by enzymatic proteolysis and microbial metabolism. Physical damage and contamination during harvesting further compromise shrimp quality. Enzymatic activities, including proteases and polyphenol oxidase, are critical in postharvest quality changes, leading to texture softening, undesirable odors, and discoloration. This chapter explores microbial spoilage of shrimp, focusing on the impact of specific spoilage organisms on shrimp quality. Major spoilage bacteria include psychrotrophic organisms such as Shewanella, Pseudomonas, Vibrio, and Acinetobacter species. These bacteria produce proteolytic enzymes and volatile compounds, resulting in texture degradation, off-odors, and discoloration. Understanding microbial dynamics and spoilage mechanisms is essential for developing strategies to extend shrimp shelf life and maintain quality, ensuring consumer safety and satisfaction. This chapter provides comprehensive insights into shrimp spoilage, highlighting the importance of aspects of shrimp spoilage.