To investigate the treatment effect of new porphyrin photosensitizer PA1 mediated photodynamic antimicrobial chemotherapy (PACT) combined with antibiotics on the rat model with severe massive traumatic infection and the mechanism of the combination treatment, 24 healthy male (clean grade) Wistar rats were used to create the massive trauma infection model. Rats were randomly divided into four groups: model control group, PACT group, antibiotic treatment group and PACT+antibiotic treatment group. There were six rats in each group. The wound healing rate and the number of bacterial colonies were detected at different time points in each experimental group during 8 d treatment. Enzyme-linked immunosorbent assay (ELISA) method was used to detect the expression of basic fibroblast growth factor (bFGF), tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in the peripheral tissues of the wound. The results show that PACT combined with antibiotic therapy can significantly reduce inflammatory reaction and bacterial colonies in rat trauma tissues, accelerate the wound healing, shorten the wound healing time, increase the content of basic fibroblast factor, and inhibit the expression of inflammatory cytokines TNF-α and IL-6. The treatment effect of PACT combined with antibiotic therapy is better than antibiotic therapy or PACT therapy alone. It suggests that PACT combined with antibiotics can treat large area traumatic infection.