Few studies have analysed postoperative risk factors in patients undergoing thoracoscopic lobectomy, including assessments of preoperative physical function. The objectives of this study were to identify predictors of postoperative deterioration of performance status and cardiopulmonary complications in cases of thoracoscopic lobectomy.Between June 2005 and October 2012, we retrospectively reviewed 188 consecutive subjects who underwent thoracoscopic lobectomy for preoperative stage I nonsmall cell lung cancer. The demographic and clinical parameters, including physical function, were analysed using a multivariate logistic regression to clarify the determinants.The percent predicted diffusing capacity of the lung for carbon monoxide, quadriceps muscle strength and pathologic stage were independent risk factors for deterioration of performance status after surgery in the multivariate analyses. Chronic obstructive pulmonary disease, 6-min walking distance and pathologic stage were also independent risk factors for postoperative cardiopulmonary complications.Our data suggest that, in addition to a greater pathologic stage, lower diffusing capacity and comorbid chronic obstructive pulmonary disease, poor physical function was associated with worse short-term outcomes after thoracoscopic lobectomy. An evaluation of preoperative quadriceps muscle strength and 6-min walk test is easily performed and may therefore be a useful predictor in cases of thoracoscopic lobectomy. @ERSpublications Evaluating quadriceps muscle and 6MWT is useful for risk assessment in cases of thoracoscopic lobectomy for NSCLC