This study aimed to examine the knowledge of patients and companions about enteral nutritional therapy (ENT) and compare similarities. This descriptive, prospective, quantitative study was conducted in a university hospital in the interior of the state of São Paulo. The study population consisted of 13 hospitalized patients and 47 companions who were interviewed over 7 months. Data regarding medical, nutritional, and nursing care were verified using electronic patient records. Data about the patients ENT was obtained through a structured questionnaire, and were compiled for this study based on the minimum requirements for ENT care in the RDC Nº 503. The statistical analysis used average and pattern deviation, median and 25-75th percentile, and number of cases and percentage. To compare proportions and agreements of the answers, the chi-square test and agreement of Kappa were used. The following was verified for patients and companions: lower correct answer frequencies in relation to the nutritional state, probe positioning test, type and quantity of prescribed diet, hand hygiene, prevention of distention/diarrhea/constipation, and different answers regarding the assessment of body weight, and knowledge of the position of the bed for feeding and hydration. It was concluded that the knowledge of patients and companions about ENT proved to be insufficient to promote patient safety. Information from companions, with few differences, is similar and in agreement with that of patients.