The spider mite, Tetranychus truncatus, is a polyphagous agricultural pest harboring various endosymbionts, such as Wolbachia and Spiroplasma. How they interact with each other in the same host is not clear. How temperature impacts the host and their interaction with endosymbionts remains largely unknown. Furthermore, little is known about the bacterial communities of Tetranychus truncatus and the molecular mechanism underlying Wolbachia regulation of host genes. This keynote speech will review and reveal new developments and discoveries on endosymbionts from this spider mite in our laboratory.