TORC1 and TORC2 protein kinases play crucial roles in maintenance of cellular homeostasis and regulation of cell growth. Rapamycin potently inhibits TORC1, but not TORC2. Budding yeast TORC2 consists of the kinase Tor2 and the accessory subunits Avo1-3, Lst8 and Bit61/2. Our 7.9Å cryo-EM structure of TORC2 reveals its architecture and the structural basis for its rapamycin insensitivity. It also sheds a new light on the functions of the non-catalytic subunits. TORC2 resides at plasma membrane where it plays a key role in maintenance of plasma membrane tension homeostasis. Increasing tension triggers re-localization of the proteins Slm1/2 from eisosomes to TORC2 and its subsequent activation. A different pathway is involved in TORC2 inactivation upon tension decrease. It requires clustering of PtdIns(4,5)P2 into micron-sized domains, which correspond to large membrane invaginations. All in all, this work deepens the understanding of how cells sense mechanical cues and communicate them to TORC2.