Sluggish hydrate kinetics and low methane storage capacity give rise to the limitation of the application of hydrate-based solidified natural gas (SNG) technology. Here, we prepared two nano-promoters of -SO3-@PSNS and -COO-@PSNS, with which, methane hydrate formation in a spiral-agitated reactor under mild conditions was evaluated. Excitingly, spiral agitation enhances hydrate nucleation and initial growth kinetics, while the nano-promoters improve hydrate later growth kinetics, and the synergy of them results in extraordinary hydrate formation kinetic under mild conditions. Large methane storage capacities of 147.28 V/V and 141.33 V/V were obtained in the systems of -SO3-@PSNS and -COO-@PSNS separately under the condition of 3.8 MPa, 275.15 K and 30 rpm, which increase by 85.07% and 77.59% comparing to that in pure water, respectively. The synergy performs better than that of spiral agitation and amino acids, and this may promote the application of SNG technology a step forward.