Low-power, nonvolatile memory is an essential electronic component to store and process the unprecedented data flood arising from the oncoming Internet of Things era. Molybdenum disulfide (MoS 2 ) is a 2D material that is increasingly regarded as a promising semiconductor material in electronic device applications because of its unique physical characteristics. However, dielectric formation of an ultrathin low-k tunneling on the dangling bond-free surface of MoS 2 is a challenging task. Here, MoS 2 -based low-power nonvolatile charge storage memory devices are reported with a poly(1,3,5-trimethyl-1,3,5-trivinyl cyclotrisiloxane) (pV3D3) tunneling dielectric layer formed via a solvent-free initiated chemical vapor deposition (iCVD) process. The surface-growing polymerization and low-temperature nature of the iCVD process enable the conformal growing of low-k (≈2.2) pV3D3 insulating films on MoS 2 . The fabricated memory devices exhibit a tunable memory window with high on/off ratio (≈10 6 ), excellent retention times of 10 5 s with an extrapolated time of possibly years, and an excellent cycling endurance of more than 10 3 cycles, which are much higher than those reported previously for MoS 2based memory devices. By leveraging the inherent flexibility of both MoS 2 and polymer dielectric films, this research presents an important milestone in the development of low-power flexible nonvolatile memory devices.