  In the two-component Majorana dark matter model, one dark matter particle can
scatter off the target nuclei, and turn into a slightly heavier component. In
the framework of a simplified model with a vector boson mediator, both the
tree-level and loop-level processes contribute to the signal in direct
detection experiment. In this paper, we report the search results for such dark
matter from PandaX-II experiment, using total data of the full 100.7
tonne$\cdot$day exposure. No significant excess is observed, so strong
constraints on the combined parameter space of mediator mass and dark matter
mass are derived. With the complementary search results from collider
experiments, a large range of parameter space can be excluded.
