Abstract: Objective： To investigate the source of cancer associated fibroblasts (CAFs). Methods：Normal fibroblasts (NFs) and CAFs were separated from normal gingival tissues and oral squamous carcinoma tissues, and then Cal27 medium was addedto NFs; we carried on the contrast research by immunohistochemistry, qRT-PCR technology, regarding NFs as negative control, CAFs as the positive control. Results：Compared with NFs, CAFs cell body was bigger, more disarranged, more rapid in growth, and with obviously different morphology. Cell immunohistochemistry showed: CAFs showed positive for vimentin, α-SMA was partly strongly positive, partly negative and FAP was strong positive, PDGFR-α was positive, CK (total) was negative. NFs was positive for vimentin, but the rest were negative. After culturing NFs with conditioned medium of Cal27, we found α-SMA was partly strongly positive, FAP was strong positive and PDGFR-α was positive. qRT-PCR showed: compared with NFs, α-SMA, FAP mRNA expression in CAFs and CM-NFs was significantly higher, and PDGFR-α mRNA expression was significantly lowered. Conclusions：Oral squamous cell cancer cells can activate the NFs to CAFs, NFs likely to be a source of CAFs.