Objective To explore the influence of different withdrawal time of trachea cannula on percutaneous dilational tracheostomy (PDT) in critically ill patients. Methods In this study, we retrospectively analyzed the clinical data of 185 critically ill patients experienced PDT, who had been admitted to the adult mixed ICU of Xiaolan Hospital of Southern Medical University from January 2015 to July 2017. The patients were divided into an early PDT group (EPDT group) and a delayed PDT group (DPDT group) according to the timing of withdrawing trachea cannula. Operation information such as operation time, blood loss and the incidence of complications were collected and compared between the two groups. Results Between the EPDT group and the DPDT group, there were no obvious differences in operation time (minutes: 6.5±2.6 vs. 7.3±3.5), amount of blood loss (ml: 5.2±2.8 vs. 6.0±3.4) or conversion to traditional operation (1.9% vs. 2.4%) (all P>0.05). Compared with the EPDT group, the DPDT group patients experienced more fluctuation of intraoperative vital signs, used more dose of sedative and analgesic drugs, and experienced higher occurrence of aspiration (18.3%vs. 5.6%), balloon burst (13.4% vs. 2.9%), guide-wire placing difficulty (11.0% vs. 1.9%) and tracheostomy cannula placing difficulty (14.6% vs. 2.9%) (all P<0.05). There were no statistical significances in postoperative complications such as postoperative-hemorrhage, pneumothorax, pneumoderm, the posterior tracheal injury or incision infection between the two groups (allP<0.05). More patients acquired postoperative pulmonary infection in the DPDT group than the EDPD group (12.2%vs. 5.8%, P>0.05), and there was no statistical significances in mechanical ventilation time between the two groups (days: 5.5±3.0vs. 6.0±2.5, P>0.05). Conclusions The operation and complications of PDT in critically ill patients are influenced by the timing of withdrawing trachea cannula. The standard procedure of withdrawing trachea cannula preoperatively may offer better clinical operability and lower technical risk.