Citrus is one of the most widely grown fruits globally, because of its remarkable organoleptic features, nutritional content and bioactive ingredients. Microbial spoilage and other factors such as physiological disorder, mechanical and physical damage, and fruit senescence are the major factors of postharvest loss to citrus industry. The postharvest losses in citrus are directly have negative impcats on the economy, environment and healths due to production of carbon emission gases. The fungal pathogens such as Penicillium digitatum, Penicillium italicum and Geotrichum candidum are the major cause of postharvest spoilage in citrus fruits. These pathogens produce different mycotoxins such as citrinin, patulin, and tremorgenic. These mycotoxins are secondary metabolites of molds; they employ toxic effects on the healths. The acuteness of mytoxin on toxicity is dependings on the extent exposure, age and nutritional status of individual. The toxicity of mytoxins are directly related to the food safety and health concern including damage DNA, kidney damage, mutation in RNA/DNA, growth impairment in childs and immune system etc. Several attempts have been made to extend the shelf-life of citrus fruits by controlling physiological decay and fungal growth which has got limited success. In recent years, nanotechnology has emerged as a new strategy for shelf life prevention of citrus fruits. The biopolymer based nano-formulations functionalized with active compounds have shown promising results in maintaining the postharvest quality attributes of fruits and vegetables by retarding the moisture loss and oxidation. This review exclusively discloses the postharvest losses in citrus fruits and their causes. In addition, the use of biopolymer based nanoformulations functionalized with active agents and their developing technologies have been also discussed briefly. The effects of nano-formulation technologies on the postharvest shelf life of citrus is also described.The finding of this review also suggest that the natural biopolymers and bioactive compounds can be used for developing nanoformulations for extending the shelf-life of citrus fruits by minimizing the fungal growth and as an alternatives of fungicides.