Abstract: Laboratory-grown (Lab-grown) diamonds are sweeping through the global diamond and jewelery markets. To ensure the stable development of lab-grown diamond market without disrupting the natural diamond one, a suite of efficient and accurate testing methods and technologies separating natural diamonds and lab-grown ones is paramount. In this article, I summarized the modern testing methods and technologies including infrared (IR) spectroscopy, fluorescence/phosphorescence imaging, inclusion studies and photoluminescence spectroscopy. Additionally, I introduced the three-dimensional (3D) fluorescence spectroscopy and time-resolved fluorescence spectroscopy used in our laboratory. Even though these new technologies may not replace some current tests, they are available to researchers and gemmologists alike as backup testing methods. Such technology reserve is essential to contribute to the stability and orderly development of the lab-grown diamond market.