OBJECTIVETo evaluate the level of knowledge and the availability of the Portuguese population to attend training in Basic Life Support (BLS) and identify factors related to their level of knowledge about BLS.METHODObservational study including 1,700 people who responded to a questionnaire containing data on demography, profession, training, interest in training and knowledge about BLS.RESULTSAmong 754 men and 943 women, only 17.8% (303) attended a course on BLS, but 95.6% expressed willingness to carry out the training. On average, they did not show good levels of knowledge on basic life support (correct answers in 25.9 ± 11.5 of the 64 indicators). Male, older respondents who had the training and those who performed BLS gave more correct answers, on average (p<0.01).CONCLUSIONThe skill levels of the Portuguese population are low, but people are available for training, hence it is important to develop training courses and practice to improve their knowledge.