Terpenoids comprise the largest family of natural products and have widespread applications. The overproduction of value-added terpenoids and the efficient mining of new terpenoids represent major challenges in the fields of metabolic engineering and natural product discovery. For terpenoid overproduction in microbial systems, in vitro reconstitution strategy guided rational engineering was emphasized, and -omics studies provide further information for targeted engineering. In addition, systematic engineering, including host and pathway engineering for terpenoid overproduction was reviewed. Furthermore, robust precursor supplies with optimized high-production hosts can also be used as an efficient platform to rapidly screen terpene cyclases and accelerate the process of mining new terpenoids.