Camel nanobody has a wide range of application prospects due to its simple structure, easy modification, and the characteristics of low immunogenicity, high stability, high specificity as well as high affinity. It is reported that nanobody with high stability could be stored and transported in more easily way compared with conventional antibodies. It can evenly refold and recover its antigen binding affinity after being denatured under polar conditions such as high temperature, high concentration organic solvents, high pressure, chemical reagents, extreme acid-base environments, and proteases. This review summarized the stability characterization of nanobody under these conditions. It is shown that nanobody can not only expand its application in the detection of targets under complex polar conditions but also enrich multiple routes of drug delivery in medical therapy, including intravenous and subcutaneous injection, nasal inhalation, and oral administration. Emphasis was made on describing the relationship between amino acid sequence, number and position of disulfide bonds, structural domains, and stability, which revealed that highly stable nanobody have common structural features such as higher net charge surfaces, disulfide bonds that limit conformational migration, framework regions with more hydrophilic amino acid substitutions, conserved hydrophobic pockets, and highly interacting structural domains. Based on these structural features, several strategies for stability structure optimization of nanobody were also discussed in this paper, including shared sequence-driven sequence repair, the substitution of easily modified amino acids, alteration of net protein charge, the introduction of unnatural disulfide bonds, and transposition of CDRs. It is expected to provide theoretical guidance on the stability regulation of nanobody to expand their wide applications as therapeutic drugs, diagnostic reagents, and biosensors.