OBJECTIVES:  Non-technical teamwork skills can be improved through simulation-based training. Steinemann et al. (2012) modified the nontechnical skills rating scale (NOTECHS) and produced the T-NOTECHS instrument to assess trauma team performance. The objectives of this study were to adapt the T-NOTECHS instrument into Finnish and to assess the reliability of the Finnish version in trauma team simulation training settings. METHODS:  The T-NOTECHS (item scores, 1=poor; 5=excellent) was translated into Finnish according to the structured translation and cultural adaptation guidelines for NOTECHS instruments (Repo and Rosqvist. Value Health 19[7]:A358). Reliability of the T-NOTECHS was assessed among 61 hospital trauma team resuscitation simulations with 193 participants. Floor-ceiling effect, internal consistency, inter-item correlation, and inter-rater reliability were analyzed. RESULTS:  Minor adaptations were done in the translation of the Finnish T-NOTECHS. Mean scores between two evaluators were 3.76 and 4.01, respectively. Chronbach’s alpha was 0.70 with inter-item correlation of 0.54. Intraclass correlation coefficient was 0.54 (95% CI, 0.34-0.70) and coefficient of repeatability was 1.53 (95% CI, 1.29-1.94). CONCLUSIONS: The T-NOTECHS instrument was successfully translated into Finnish. The Finnish version of the T-NOTECHS proved to have fair reliability. The Finnish T-NOTECHS can now be used to assess efficacy of trauma team performance in real-life resuscitations and in resuscitation simulation training.