In this paper, Anaerobic Baffled Reactor (ABR) was applied to treat the synthetic wastewater in the matrix of starch and glucose. the reactor was started using low loading start-up , VLR controlled at 0.59~11.05kgCOD/m3•d, there are some granular sludge appeared after running 18 days. The figure and size of granular sludge in each compartment revealed different characteristics due to the changing of OLRs and shear force between gas and liquid in each compartment. The COD removal efficiency was higher than 90% and steady when the reactor’s start-up finished.When the anaerobic granular sludge appeared in the reactor, the VLR was 1.29kgCOD/(m3•d)、COD removal efficiency was 83％、hydraulic surface loading was 0.078m3/m2.h and an HRT was 30h. The VLR had remarkable influence on COD removal efficiency、VFA、pH and ALK. When VLR was 5.57kgCOD/(m3•d), COD removal efficiency and ALK were the minimum, VFA in the outflow exceeded 1000mg/L, reactor’s efficiency decreased .The reactor recovered after adjusting VLR and ALK value. Compared with the third and fourth compartments, the first and second compartments were less sensitive to changing of VFA. When pH deviated from adapt range, the COD removal efficiency was decreased obviously, so pH value was kept in the range of 6.2 to 6.5 for the later stage of experiments.