Objective:To determine the value of lung function, cannula diameter and swallowing function in predicting the success of tube blocking in patients with severe neurological diseases so as to standardize the tracheal decannulation procedure.Methods:The tracheotomy tube blocking of 28 neurological disease patients was studied retrospectively. Before their tracheotomy tubes were blocked the patients′ lung function and swallowing function had been evaluated, and sputum volume and endotracheal tube diameter had been recorded.Results:The five most useful predictors of success in tracheotomy tube blocking were FVC, FVC%, FEV1 (L), FEV1 (L), FEV1 (L) and PEF(L/S). Their OR values were all greater than 1, indicating good predictive power. FEV1 and PEF showed the best predictive power, with OR values of 81.70 and 27.77, respectively. There was no significant difference between the two groups in terms of the other indicators. FEV1 predicted that the best truncation value for tracheotomy tube blocking success is 0.42L, achieving a sensitivity was 100% a specificity of 63.64%, and a correction index of 0.636.Conclusion:FEV1 values can be a useful predictor of successful tracheotomy tube blocking. Using it should improve the success rate of tube decannulation.