For the past 10 years, influenza vaccination coverage rate in Poland remains at a low 3% threshold. This low rate may be related to the unsatisfactory knowledge of vaccination, influenza, and misperception of health risks in the general population. To examine these issues, we used an online questionnaire consisting of 12 closed questions. The basic knowledge on influenza and vaccination was examined. The questionnaire was completed by 1669 persons, mostly young women. Generally, 73% of respondents passed the threshold of 70% correct answers, but important gaps in their knowledge were identified concerning the persons at risk of developing the infection (7.9% of correct answers) and the timing of vaccination (8.4% of correct answers). Although most respondents did identify the etiologic agent correctly (91.1% knew influenza is caused by a virus), only 12.3% knew that the vaccines registered in Poland contain fragments of viruses or its antigens, while 63.1% thought the vaccines contain live bacteria. In conclusion, the knowledge on influenza vaccination is deficient in the general population. Education on immunization should be prioritized to increase vaccination coverage rate in Poland.