  In this work, we study the response of single layer Thick GEM (THGEM)
detector to p/${\pi^+}$ at E3 line of Beijing Test Beam Facility. In our
experiment, the drift gap of THGEM Detector is 4mm, and the working gas is
Ar/3% iso. Result shows at the momentum 500MeV/c to 1000MeV/c, detection
efficiency for p is from 93% to 99% in a relatively lower gain($\sim$2000),
while the detection efficiency for ${\pi^+}$ is slightly lower than that for p,
which is from 82% to 88%. Meanwhile, simple Geant4 simulations have been done,
and results of beam test are almost consistent with it. We preliminarily study
the feasibility of THGEM detectors as sampling elements for Digital Hadronic
Calorimeter(DHCAL), which may provide related reference for THGEM possibly
applied in Circular Electron Positron Collider(CEPC) HCAL.
