The influence of steel fiber spacing （2， 4， 6， 8， 10 and 12 mm） on the pullout performance of steel fiber in ultra-high performance concrete（UHPC） matrix was studied by the double steel fiber pullout test. Six sets of double fiber specimens and one set of single fiber specimens embedded with 0.2 mm copper-plated straight round steel fibers were fabricated. Based on the parameters of the pullout load-slip curve， average bond strength， and maximum pullout stress， and combined with scanning electron microscope （SEM）， the micro-appearance of steel fibers after pulled out， the micro-morphology of UHPC matrix tunnel and the failure part were observed. The influence of steel fiber spacing on the pullout performance between UHPC matrix and steel fibers was analyzed. The steel fiber pullout test results showed certain discreteness； the maximum pullout load of double fibers pullout test was less than twice that of the corresponding single fiber pullout test. The steel fiber and UHPC matrix tunnel had different degrees of damage. The scratches on the surface of steel fiber and the holes in the matrix tunnel of double fiber specimen were more serious than those of the single fiber specimen， while the inner wall of the single fiber specimen was relatively complete.