The limited availability of autografts and failure of small diameter synthetic vascular grafts has stimulated continuing efforts to develop small diameter vascular grafts based on natural materials. The small diameter collagen tubes were extruded using bovine collagen type I. The biodegradation rate was determined and compared for small diameter collagen tubes crosslinked with glutaraldehyde and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) and Nhydroxysuccinimide (NHS) to evaluate physio-chemical properties. The samples were also evaluated for their surface area and porosity using mercury porosimeter. The noncrosslinked tubes almost completely degraded after 2 hours. The tubes crosslinked with EDC/NHS degraded slower than the ones crosslinked with glutaraldehyde. The biodegradation rate seemed to be dependent on concentration of crosslinking agent and collagen suspension. The in-vitro model equation for small diameter collagen tubes showed linear behavior. The porosity characterization study showed that EDC/NHS treated tubes are more porous and have more surface area than glutaraldehyde treated tubes. Future work on this area will be to study biodegradation rate for small diameter collagen tubes over longer period of time.