Understanding and control of many-body collective phenomena such as charge density wave (CDW) and superconductivity in atomically thin crystals remains a hot topic in material science. Here, using first-principles calculations, we find that 1T-HfTe2 possessing no CDWs in the bulk form, unexpectedly shows a stable 2 × 2 CDW order in the monolayer form, which can be attributed to the enhancement of electron–phonon coupling (EPC) in the monolayer. Meanwhile, the CDW induces a metal-to-insulator transition in monolayer 1T-HfTe2 through the accompanying lattice distortion. Remarkably, Ising superconductivity with a significantly enhanced in-plane critical field can emerge in centrosymmetric monolayer 1T-HfTe2 after the CDW is suppressed by electron doping. The Ising paring is revealed to be protected by the spin–orbital locking without the participation of the inversion symmetry breaking which is a must for conventional 2H-NbSe2-like Ising superconductors. Our results open a new window for designing and controlling novel quantum states in two-dimensional (2D) matter.