Vector control of dengue is widely used in preventing the disease transmission worldwide. The growing demand in reducing the use of chemical insecticides has provided imputes to explore safer alternatives. Biological control of dengue vector is the suitable approach to this problem. Myco-biocontrol using Aspergillus terreus was evaluated for its potential larvicidal activity against Aedes aegypti and safety to nature. Local strain of A.terreus was isolated from Jallo forest, Lahore, and its efficacy against the 3^rd and 4^th instar larvae of A. aegypti was assessed.A.terreus was mass cultured in potato dextrose agar (PDA) medium under controlled laboratory conditions. Bioassay of the prepared fungal suspension was applied against the larvae and the mortality rate was observed after 24, 48 and 72 hours. The experimental groups consisting of 10⁷,10⁶ and 10⁵ conidia mL^-1 showed the mortality rate of 90%, 65% and 50%, respectively. The LC₅₀ values after 24, 48 and 72 hours was recorded as 8.1E+6, 4.27E+5 and 1.99E+4, respectively. Besides the efficacy of A. terreus against dengue vector, the current paper evaluatedits safety against plants, fish and indoor air for its consideration as safe to natural environment.A.terreus showed no potential side effects on fish, plants and indoor air proving it safe for the environment.