The minimum quantity lubrication (MQL) approach is used for improving tool life at a low cost, and it is environmentally friendly. When compared to traditional flood cooling technology, the flow rate in MQL is thought to be 10,000 times lower. The workpiece’s surface smoothness is enhanced by continuous chip formation during turning, but because the tool is always in touch with the chip, a crater wear zone is formed on the rake face due to high friction and thermal stress. While adding nanoparticles to MQL enhances cutting performance, a high concentration of these nanoparticles causes burr adhesion and decreased chip evacuation capability due to the agglomeration of nanoparticles, which affects the surface finish of the workpiece. A novel “coconut-oil-based SiC–MWCNT nano-cutting fluid for a CBN insert cutting tool” is proposed in this approach to overcome these issues. Silicon carbide (SiC) and multi-walled carbon nanotubes (MWCNTs) are added to coconut oil with an appropriate volume fraction for better lubrication. The thermal properties of the proposed nano-cutting fluid are compared with those of some existing nano MQL cutting fluids, and it was found that the MQL cutting fluid under consideration exhibits an elevated thermal conductivity and convective heat transfer coefficient that efficiently reduce tool temperature and improve tool life. The comparative study between the Finite Element Simulation using computational fluid dynamics (CFD) predicted variation in tool temperature and the corresponding experimental values revealed a remarkable alignment with a marginal error ranging from 1.27% to 3.44%.