[Aim] Three Bacillus thuringiensis Berliner insecticidal proteins were assessed to explore their effects on non-target insect corn leaf aphid (CLA), Rhopalosiphum maidis (Fitch) to provide scientific evidence on the environmental safety of Bt maize in the agroecosystem. [Method] Bioassays on the CLA were conducted using three insecticidal proteins, Vip3Aa19, Cry1Ab and Cry1Ah, added to an artificial diet. Accordingly, phosphate buffered saline (PBS) and Na₂CO₃ were used as buffer-base controls (negative control), casein (CS) was used as a neutral control, and two levels concentrations of neem oil (Neem-L and Neem-H) were used as positive controls. Four life table parameters, i.e. survival rate, developmental duration, percentage of alatae, and number of offspring were recorded. [Result] The ST₅₀ (media survival time) value (8.3-9.6 d) of the CLA was not affected by the treatments with either individual Bt protein or CS in comparison with the negative control. The development time of the nymphs was shorter (1.0-2.9 d) and number of offspring was greater on the diet incorporated with CS, and individual Bt protein, respectively when compared to the negative control. High percentage of alatae developed on the diet incorporated with Vip3Aa19, Cry1Ab and CS than that on the negative control. with the positive controls had significant insecticidal activity against corn leaf aphid. ST₅₀ was 3.2-4 days after challenge at Neem-L. No nymphs could survival at day 4 at Neem-H. There were also no offspring produced in two positive controls. [Conclusion] Three Bt proteins, Vip3Aa19, Cry1Ab and Cry1Ah, did not show any significant effects on the CLA in terms of survival/mortality, but they did show remarkable positive (nutritional) effects as same as CS on growth rate and reproduction of the CLA comparing with their buffer-based control.