In vector control, plant extracts are increasingly provided numerous sources of phytochemicals utilized on mosquito control. Essential oils such as Lippia alba have shown their effectiveness against insects. Our present study aims to show the toxicity of L. alba essential oil on Anopheles gambiae larvae and to demonstrate the histological damage. The larvae were exposed to serial concentrations from 200 ppm to 1000 ppm. Mortalities were recorded after 24 hours exposure to determine lethal doses LD50 and LD90. Larvae treated with LD90 were fixed at 6h, 12h, and 24h to show the process of histological degradation. After 24 hours exposure, the results revealed that mortalities were 6.66%, 5%, 61.33%, 91.66%, and 91.66% for respectively 200, 400, 600, 800, and 1000 ppm doses. Fisher's test revealed that there was no significant difference in mortality between the control and low doses (200 ppm and 400 ppm), (p = 1). On the other hand, mortalities were significant between the control (0 ppm) and doses ≥ 600 ppm (p = 0.0006). The lethal doses LD50 and LD90 determined using the Muller and Tinter formula were 554.4 ppm and 788.2 ppm, respectively. The histological examnition revealed that, the product acts between 6h and 24h through with progressive destruction of the nervous system, muscle tissue, adipose tissue, and digestive tract. It appears that L. alba essential oil constitutes a product with a larvicidal effect and could be evaluated in a natural breeding sites against vector mosquitoes.