It is known that insecticide produces problems to human being and environment. So, new alternatives to fight against insects, such as mosquitoes are being evaluated. Among them is the use of plant chemicals, which are more effective and less harmful to environment. Therefore, our study evaluates for first time the larvicide activity of noni (Morinda citrifolia) on the mosquito (Aedes aegypti) which is the vector of dengue. To achieve our goal we prepared alcoholic solutions of fruits (125mg/L, 145 mg/L, 165 mg/L, 185 mg/L, 205 mg/L) and evaluated them on IV instars larvae. The mean (LC50) and high (LC90) concentrations were 151.9 mg/L and CL90: 195.5 mg/L, respectively. We reported larvicide activity of noni on Aedes aegypti larvae and we discussed about the possible toxic chemicals that produce this effect. Even though of toxic activity, it was less than another plant species which have bee studied previously. The possible advantages of the use of this plant species for controlling Aedes aegypti larvae is discussed.