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Low-cost catalysts are of great significance for the batch synthesis of carbon nanotubes. In this study, the low-cost red soil was directly used as a natural catalyst to catalyze the growth of multi-walled carbon nanotubes (MWCNTs). The results of SEM, TEM, Raman, TG and carbon yields of the products consistently showed that 400 °C calcined red soil lead to high quality MWCNTs growth, the Raman I G /I D of the product is 1.66, which indicates that the product has exceeded the graphitization of many industrially synthesized MWCNTs. The high catalyzation efficiency may be attributed to the fact of composition characteristics that red soil lacks alkali metals and alkaline earth metals but is rich in iron and aluminum oxide, making the composition of red soil similar to the catalyst composition used in the synthesis of carbon nanotubes by common chemical vapor deposition method. Meanwhile the impurity content is less than other natural catalytic materials. The porous structure formed after proper calcination has also played a positive role to the catalytic growth of MWCNTs, which improved catalyst utilization by facilitating the gas phase diffusion. We explored a technique for synthesis of high-quality MWCNTs at low cost using soil as a catalyst. Unlabelled Image • A low-cost synthesis of carbon nanotubes using the red soil as catalyst. • Red soil calcined at 400 °C lead to high quality MWCNTs growth. • The I G /I D of the product is 1.66,which was higher than that of many commercially prepared MWCNTs. • Red soil showed the most effective catalyst for the growth of CTNs compared with other soils. [ABSTRACT FROM AUTHOR]