Summary In this study, we aimed to evaluate the nematicidal activity of cinnamon bark extracts (CE) and chitosan (Cs) against Meloidogyne incognita and Pratylenchus coffeae under pot and field conditions. In the pot experiments, CE mixed with Cs effectively inhibited M. incognita and P. coffeae infection on robusta coffee plants. The formulations applied, CE:Cs = 8 mg:30 mg, CE:Cs = 16 mg:60 mg and CE:Cs = 16 mg:60 mg per pot, significantly reduced the gall index and nematode number in 5 g of root and 100 g of soil. In addition, the application of CE:Cs = 48 mg:180 mg CE:Cs = 80 mg:300 mg and CE:Cs = 112 mg:420 mg plant−1 effectively reduced root gall formation and nematode density in roots and soil compared with the non-treated control under field conditions. Nematode density in the roots was positively correlated with the rate of yellow leaf disease. These results suggest that cinnamon mixed with chitosan may be used as an effective eco-friendly pesticide against plant-parasitic nematodes.