This SOP describes the procedure for determining the extensibility of pounded yam using the Kieffer dough extensibility method. The SOP also reviews the procedure for preparation of pounded yam by adjusting the dry matter of the pounded yam to 30% during pounding. The SOP reviewed the existing method of preparing pounded yam from Dioscorea rotundata and Dioscorea alata genotypes mechanically by modifying the method through adjusting the dry matter of the pounded yam to 30% in order to determine the amount of water to be added during pounding. Results showed that the extensibility and area under extension curve were the most discriminant textural parameters while extensogram peak force was the least discriminant textural parameter. The method was able to differentiate between the extensibility of D. alata genotypes and D. rotundata genotypes. The precautions required to conduct the procedure correctly and the statistical recommendations of minimum number of observations to be conducted are given.