Introduction: Diabetes is a public health problem and tools to evaluate health literacy in among people living with diabetes are scarce.  It is difficult to find tools to estimate the levels of access, understanding, evaluation and application of information about diabetes. Here, it is proposed to use a questionnaire called “Health Literacy in Diabetes long version (HLD-long). Methods: It was a methodological study conducted in a Brazilian municipality from 2016 to 2021, whose population is approximately 400,000 people. The questionnaire, consisting of 155 items, was based on a literature review and considered the theoretical model proposed by Sørensen and collaborators. The quality assessment was designed according to the Cosmin checklist. After a simple random drawing from the 73 primary care centers, 5 centers were chosen and the survey was answered by 340 people living with diabetes. The study consisted of four stages comprised four phases: 1) Creating the survey (HLD-long); 2) Evaluation of the questionnaire content by a committee of experts to ascertain the adequacy and coherence of the items; 3) Review of the final version by the committee 4) Estimation of reliability using Cronbach's alpha test (internal consistency) and test-retest / reproducibility (simple and weighted kappa).  It contains 155 questions or items that propose the assessment of access by estimating number of people / professionals, subjects and printed / electronic / digital materials accessed by the participants; that allow the characterization of literacy (access / understanding / evaluation / application) according categoric prodissional or people who offered the information. A committee of experts verified the questions' relevance and adequacy. Results: The (HLD-long); showed content validity and reliability. Psychometric analysis (exploratory factor analysis, correlations between distinct surveys, with presentation of interpretability) of short versions and cutouts of the long version have been done. Conclusion: Psychometric assessments were made and associated with the proven content validity and reliability already shown suggest that the (HLD-long) among other versions coming from this survey, could be used in primary health care in future studies to estimate literacy levels,  for the purpose of to the elaboration of health policies consistent with reality.