According to "Never Events", insulin administration errors are serious preventable adverse events that should not have occurred if adequate preventive measures had been implemented. The event "insulin administration error" is on the ANSM list published in 2012. The National Health Service's (NHS) "Never Events insulin" has developed a module on insulin therapy management entitled "Preventing insulin-related medication errors". Proper use and knowledge of insulin management can prevent these events. Our study presents the results of a survey designed to assess both the knowledge of healthcare personnel and a group of diabetic patients in the Souss Massa region of Morocco. Our survey was an opportunity to re-educate our patients and review the knowledge of a group of staff interviewed, underlines the important deficit in knowledge and practice of nursing staff and insulin-treated patients, suggests that urgent intervention should be considered, particularly with young nursing staff, and also to review the therapeutic education of insulin-treated diabetics in order to improve their knowledge and better prepare them for the advent of new generations of insulin.