In this study, LaFeO3 perovskite orthorhombic-shaped nanospheres and holmium-doped LaFeO3 nanomaterials were prepared by a simple co-precipitation method. Their composite was made with carbon nanotubes (Ho-LaFeO3/CNTs) via an ultrasonication route. The X-ray Diffraction spectroscopy (XRD), Fourier Transform Infrared spectroscopy (FT-IR), Scanning Electron Microscopic analysis (SEM), Electrochemical Impedance Spectroscopy (EIS), and UV–visible spectroscopy, were done to analyze the prepared nanomaterials. Tauc plot was used to find the bandgap of prepared samples. The photocatalytic efficiency of prepared nanocrystals under visible light irradiation was investigated by degrading Congo red dye (colored pollutant) and Benzoic acid (colorless pollutant). The prepared Ho-LaFeO3/CNTs nanocomposite showed the highest photocatalytic efficiency compared to LaFeO3 and Ho-LaFeO3 samples as it degraded 83% Congo red and 69.5% Benzoic acid in 140 min, respectively. Carbon nanotubes helped in trapping the electrons and lower the recombination rate of e-/h+ pairs and as a result, increase the photocatalytic activity.