In order to define the tensile behavior of reactive powder concrete-filled steel tube (RPCFST), the strain behavior and failure modes of RPC-FST were investigated by testing a total of 40 specimens under direct tension load with different curing temperatures, steel fiber volume contents and thicknesses of steel tube. It is shown from the test that, axial tension load-strain relationship of PRCFST is similar to that of concrete-filled steel tube (CFST); the cracking load is about 25 percent of peak load; the ultimate tensile resistant of RPC-FST can be specified by the method for CFST, which is simple and reliable, and can provide reference for engineering design.