The sequential screening procedure to select items within a given specification without measuring the performance variable Y by allocating k screening variables which are highly correlated with Y into r stages has become a very important issue in manufacturing industries. Wu and Cheng proposed a two-sided screening procedure by weighting the screening variables twice. Since the weights assigned to each screening variable in the first stage may not be reasonable, we propose the modified procedure by only weighting the screening variables once. The numerical comparison of the modified procedure with the old procedure shows that the modified procedure has smaller total inspection cost (TIC) than the old procedure and the proposed method is simpler to be implemented by users. We consider an expected total cost (ETC) which is the sum of the expected cost for consumer’s risk and the total inspection cost as the criterion for the selection of optimal allocation combination for sequential screening procedure (SQSP). A software is developed to search the optimal allocation combination based on the criterion of minimum TIC or ETC. At last, a real life example is given to illustrate the modified screening procedure.