For facial soft tissue augmentation or wound coverage using tissue-engineering technology, cultured fibroblasts have been most commonly used as key cells and their properties have been extensively studied. Clinical strategies based on human cultured fibroblasts, however, require Food and Drug Administration (FDA) approval for the facilities and the procedures used and time-consuming culture. Adipose tissue-derived stromal vascular fraction (SVF) cells may be a reliable alternative to fibroblasts because they are easily harvested by liposuction and do not require culture or FDA approval. No quantitative standard governing their use has, however, been issued. The purpose of this study was to quantitatively compare matrix-forming abilities of SVF cells and fibroblasts. Human dermal fibroblasts were obtained from the dermis of 10 healthy adults and cultured, and SVF cells were obtained from 10 patients who underwent liposuction. Monolayer and suspension cell cultures were performed using both cell types for 3 days. Cell proliferations, collagen synthesis levels, and glycosaminoglycan levels were compared using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, a collagen type I carboxyterminal propeptide enzyme immunoassay, and the Blyscan Dye method, respectively. Cell proliferation ratios (fibroblasts versus SVF cells) in monolayer and suspension cultures were 1:0.75 and 1:0.99, respectively; collagen synthesis ratios in monolayer and suspension cultures were 1:0.50 and 1:0.52, respectively; and glycosaminoglycan production ratios were 1:0.70 and 1:0.74, respectively. The results of this in vitro study indicate that SVF cells have 50-74% of the matrix-forming ability of fibroblasts.