Background The extraordinary situation caused by the onset of COVID-19 has meant that at prehospital level, the number of treatments, profle and time taken to respond for treating time-dependent pathologies has been greatly afected. However, it is not known whether the prehospital profle of polytrauma patients (PTP) has been afected. Objective To determine diferences in the epidemiological characteristics and the clinical variables of prehospital polytrauma patients during the frst wave of the COVID-19 pandemic in Catalonia. Methodology Analytical cross-sectional study. The number of prehospital activations and the clinical and epidemiological characteristics of polytrauma patients attended by the Emergency Medical System (EMS) of Catalonia, were compared for the period between 15 February and 15 May 2020 and the same period in the previous year. Priorities 0 and 1 are assigned to the most severely injured patients. An analysis was conducted using logistic regression and nonparametric tests. Results 3023 patients were included. During the 2019 study period, 2045 (67.6%) patients were treated; however, during the pandemic period, 978 (32.4%) patients were treated, representing a 52% decrease (p=0.002). The percentage of patients presenting priority 1 was higher during the pandemic period [240 (11.7%) vs 146 (14.9%), p=0.032]. The percentage of priority 0 and 1 patients attended by a basic life support unit increased [201 (9.8%) vs 133 (13.6%), p =0.006]. The number of trafc accidents decreased from 1211 (59.2%) to 522 (53.4%) and pedestrian-vehicle collisions fell from 249 (12.2%) to 92 (9.4%). Regarding weapon-related injuries and burns, there was an increase in the number of cases [43 (2.1%) vs 41 (4.2%), and 15 (0.7%) vs 22 (2.2%), p=0.002 and p<0.001, respectively]. Hospital mortality remained unchanged (3.9%). Conclusions During the frst wave of the pandemic, the number of polytrauma patients decreased and there was a change in the profle of severity and type of accident.