Objective:The quantitative effects of formulation and processing variables affecting the binding properties of Chinese yam starch (Dioscorea oppositifolia)in chloroquine phosphate tablet formulations have been investiga-ted in comparison with c starch using a 23 factorial experimental design.Methods:Chinese yam starch,re-presenting the lowlevel,and c starch,representing the highlevel were used as binders at concentra-tions of 2.5 %w/w and 10 % w/w in chloroquine phosphate tablet formulations.The mechanical properties of the tablets,measured by the tensile strength (T)and brittle fracture index (BFI)as well as the release prop-erties measured by the disintegration time (DT)and dissolution time (t8 0-time for 80 % drug release),were used as assessment parameters.Results:The ranking of the individual coefficient values for the formulations on T was D >N C,on BFI was N >D C,on DT was D >N >C and on t8 0 was C >N >D while the ranking of the interaction coefficient on T was N-D >C-D  N-C,on BFI was N-D >N-C =C-D,on DT and t8 0 was N-C >N-D >C-D.Changing the binding agent from Chinese to c starch,led to a decrease in T,DT and t8 0 but increase in BFI of the tablets.There were significant (P <0.001)interactions between the nature of binder,N and the other two variables,C and D.Conclusion:The result showed that Chinese yam possessed stronger binding capacity than c starch and could be useful as an altative binder when tablets with high mechanical strength with minimal problems of lamination,and slow release are required.