Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on concentrated liquid l-lysine (base) and l-lysine monohydrochloride (HCl) produced using Corynebacterium caseiKCCM 80190 when used as nutritional additives in feed and water for drinking for all animal species. The active substance is l-lysine. The production strain is genetically modified. It does not carry acquired antimicrobial resistance genes and no viable cells of the production strain nor its DNA were detected in the final products. Therefore, the additives do not pose any safety concern regarding the genetic modifications. Concentrated liquid l-lysine (base) and l-lysine HCl produced by C. caseiKCCM 80190 do not represent a risk for the target species, the consumer and the environment. From the results of studies on the safety for the user of concentrated liquid l-lysine (base) and l-lysine HCl produced by a different production strain, it was possible to conclude on the safety for the user of the products under assessment. Concentrated liquid l-lysine (base) produced by C. caseiKCCM 80190 is considered hazardous by inhalation, not irritant to skin and eyes and it is not a skin sensitiser. l-Lysine HCl produced by C. caseiKCCM 80190 is considered hazardous by inhalation, it is not irritant to skin but mildly irritant to eyes and it is not a skin sensitiser. Concentrated liquid l-lysine (base) and l-lysine HCl are considered efficacious sources of the essential amino acid l-lysine for non-ruminant animal species. For the supplemental l-lysine to be as efficacious in ruminants as in non-ruminant species, it would require protection against degradation in the rumen.