The lubricant choice is a critical factor in the high-speed machining process, and it can impact the machining surface quality and also the ultimate material properties. This paper investigates the microstructural surface finishing and heat generated during the high-speed cutting process (machining speed 3800 RPM) of 2219 aluminum alloy. The study examines flood coolant and five different nanofluids made by synthesizing 0.2% to 2% concentration of Al2O3 nanoparticles into ultra-food-grade mineral oil utilizing nanoparticle-enhanced minimum quantity lubrication (MQL) technique. In the MQL method, unlike the current known cooling fluid systems, the nanofluid provides a thin lubricant film that leads the heat created by friction to be transmitted to the chips and exits the interface. Also, the small amount of lubricant used for MQL makes this technique more environmentally friendly. The study revealed the chemistry between the MQL of choice and the corresponding surface finishing. As a result, the nanofluid with a 0.5% concentration of nanoparticles has the most optimal machining result. Furthermore, increasing nanoparticle concentration does not indicate any further improvement in the result. The results of this study could be instrumental to developing environmental-friendly machining solutions for aluminum alloys at commercial scales.