The fruit fly Drosophila melanogaster (Meigen) (Diptera: Drosophilidae) is often used in various biological, molecular, and toxicological studies. Sodium tetraborate, a boron compound, was added to the artificial diet of developing D. melanogaster to determine its effects on adult longevity and fecundity. Insects reared from first instars to adults on diets containing 10, 30, 150, 300, or 400 mg/liter sodium tetraborate showed that the highest concentration (400 mg/liter) significantly reduced female longevity (31.65 ± 4.02 [mean ± SD] d for the controls versus 1.87 ± 0.30 d for 400 mg/liter) and male longevity (32.80 ± 1.96 d for controls versus 3.57 ± 0.42 d for 400 mg/liter). Females from the control diet produced 9.46 ± 0.57 (mean ± SD) eggs per female, whereas those fed on a diet containing 300 mg/liter produced only 1.92 ± 0.30 eggs per females. These results expand our knowledge of the impact of sodium tetraborate on various insects and indicate that boron compounds should be further investigated to ascertain their potential as an alternative control tactic for pest insects.