Using the latest AMS-02 cosmic ray antiproton flux data , we search for potential dark matter annihilation signal .
The background parameters about the propagation , source injection , and solar modulation are not assumed a priori , but based on the results inferred from the recent B/C ratio and proton data measurements instead .
The possible dark matter signal is incorporated into the model self-consistently under a Bayesian framework .
Compared with the astrophysical background only hypothesis , we find that a dark matter signal is favored .
The rest mass of the dark matter particles is \sim 20 - 80 GeV and the velocity-averaged hadronic annihilation cross section is about ( 0.2 - 5 ) \times 10 ^ { -26 } cm ^ { 3 } s ^ { -1 } , in agreement with that needed to account for the Galactic center GeV excess and/or the weak GeV emission from dwarf spheroidal galaxies Reticulum 2 and Tucana III .
Tight constraints on the dark matter annihilation models are also set in a wide mass region .