Thermophilic microorganisms hold advantages including resistance to contamination, reduced cooling costs, and enhanced enzyme activity, positioning them as promising candidates for next-generation industrial biotechnology. However, the inactivity of tools developed for mesophiles hampered the development of thermophiles. By investigating the expression of the T7 RNA polymerase (T7RNAP) in Parageobacillus thermoglucosidasius , we found that the low expression levels of heat-shock proteins in thermophiles contribute to the inactivity. Specifically, we identified HSP33, DnaK/J, and GroS/L as key chaperones that synergistically enhance the folding of T7RNAP. Through understanding the potential recruitment effect of HSP33 on DnaK/J, we de novo designed an HSP33-based tag to improve the activity of T7RNAP to a greater extent. To further enhance this recruitment effect, we conducted a systematic collection of the core element HSP33 through evolutionary analysis across various thermophilic microorganisms, and screened a superior tag that significantly boosted the activity of T7 RNA polymerase. Ultimately, we demonstrated that the developed Chaperone-Tag system also improved the activity of T3 RNA polymerase in this strain, highlighting the broad applicability of our strategy.