Effect of algal derivatives or their components on suppression of the root-knot nematode (RNK, Meloidogyne incognita) has few studies. So, the application of the nematicidal potential of 3 microalgae, Scenedesmus obliquus (SO), Chlorella vulgaris (CV) and Anabaena oryzae (AO), alone or in combination were tested against M. incognita on banana plants grown in 30 cm pots soil. All algal tested materials significantly (p < 0.05) reduced the number of second stage juveniles (J2s) in the soil (52.6%), compared with the inoculated check. Similarly, the algal treatment (AO + CV) was found to be the most clearly positive effect on reducing of J2s of M Incognito in the soil comparing to those of control with nematodes. However, the presented plant girth (shoot weight, shoot length, root weight, root length, corm weight) had a maximum impression in the all tested materials. Shoot weight of most plants was much higher than that of the check. Interestingly, the obtained results from Fourier transform infrared spectroscopy (FT-IR) denoted that the chemical content of the tested plants changed according to various treatments. The highest components of total phenolics and the highest antioxidant vigor were found in the plants treated with AO + CV + SO. Overall, the previous algal treatments were forceful protector and had a potent stimulating effect on the plant girth and inhibition of M. incognita in susceptible banana plants.