Burns are traumatic pathologies responsible for significant morbidity and mortality, which is considered as a public health problem, particularly due to their frequency, potential severity, the side effects they can cause as well as their treatment and prevention. In fact, according to the World Health Organization (WHO), approximately 11 million people suffer from burns each year and 180,000 deaths are due to these injuries. Although the development of modern medicine has resulted in the coming of innovative drugs and procedures, the problem of accelerating healing with the least possible side effects still remains in addition to socio-economic and cultural reasons which are added to that. A renewed interest in medicinal plants as well as traditional medicine for curative purposes is currently being observed to treat burns. It is in this context that our study takes place, the essential objective of which is to evaluate the potentially healing and toxicological effect of crude Urtica dioica leaves extract through an in vivo study while exploring a possible antibacterial effect of this plant. Our results demonstrated the safety of ethanolic extract of nettle, in fact, the evaluation of acute toxicity of Urtica dioica ethanolic extract revealed no mortality or morbidity of female albino Wistar rats treated topically with single doses of extract (1 g/kg, 2 g/kg and 5 g/kg). During the 14 days of observations, no sign of intoxication or physiological change in the animal was recorded. The use of nettle leaf extract on 3rd degree thermal burns inflicted on male Wistar rats showed significant anti-inflammatory and healing activity, as well as a proliferative effect on hairs through activation skin hair follicles compared to untreated groups. However, no antibacterial activity of nettle extract was observed with the type strains tested. It can be concluded that the extract of our plant has remarkable healing effects with non-toxic effect on the organism.