A bench scale (571 mL capacity) packed-bed thermogravimetric analyzer (PB-TGA) witha condensate measurement unit was designed, built, characterized, and tested to study both the solid decomposition and condensate formation characteristics during the pyrolysis of biomass at a constant heating rate. This attempts to satisfy limitations of current analytical systems such as high sensitivity to particle homogeneity, the limited ability to observe bio-oil formation characteristics, and limitations in carrier gas based mass transfer. Weight changes in both the solid phase and condensate were measured from 25C to 600C at 3 C/min with a nitrogen carrier gas owrate of 0.25 L/min . The PB-TGA was tested and compared to a commercially available analytical TGA using a cellulosic powder and pine-pellets. The PB-TGA experiments exhibited increased char yield and thermal lag, more symmetric and lower magnitude dierential thermogravimetric (DTG) curves, and dierences in reaction kinetic parameters.