Activated hepatic stellate cells (HSCs) are a potential source of gelatinase A, which accumulates in fibrotic livers. Progelatinase A activation requires its binding to a complex of membrane‐type matrix metalloproteinase (MT‐MMP) and tissue inhibitor of metalloproteinases (TIMP)‐2. These studies examine gelatinase A, MT1‐MMP, and TIMP‐2 synthesis by HSCs during activationin vitroand the potential role of gelatinase A in promoting HSC proliferation. Gelatinase A, MT1‐MMP, and TIMP‐2 messenger RNA (mRNA) were all upregulated in HSCs activated on plastic over 5 to 14 days. Gelatinase A expression was maximal at 7 days of culture, coinciding with the peak of HSC proliferation and the onset of procollagen I and α‐smooth muscle actin (α‐SMA) mRNA expression. Active forms of gelatinase A of 62 kd and 66 kd were secreted by activated HSCs and reached a maximum of 12.1% of total enzyme in 14‐day culture supernatants. Treatment of HSCs with concanavalin A (con A) induced activation of MT1‐MMP and enhanced secretion of activated gelatinase A, which reached a maximum of 44.4% of the total enzyme secreted into culture supernatants using 30 μg/mL con A. [¹⁴C]‐gelatin degradation assays confirmed the presence of gelatinolytic activity in activated HSC supernatants, which reached a maximum level at 7 days of culture. Antisense oligonucleotide inhibition of endogenous progelatinase A production, or the MMP inhibitor 1,10‐phenanthroline inhibited ³H‐thymidine incorporation into HSC DNA by greater than 50%. We conclude that HSCs produce progelatinase A during activation in vitroand activate this enzyme coincident with MT1‐MMP and TIMP‐2 synthesis. Gelatinase A activity is required for maximal proliferation of HSCsin vitrosuggesting this metalloproteinase is an autocrine proliferation factor for HSCs.