The latest machining processes have motivated the development of new coolants. The aim of this study is to examine the effect of hybrid coconut oil based nanocoolant influence the surface roughness of AA6061-T6. The excellent mechanical attributes of the material such as enhanced ultimate tensile strength, improved Rockwell hardness, and intrinsic ductility place this material amongst the vital candidates that are fit for precision machining. The work endeavors to investigate the correlation between effective oil-based lubrication efficiency and a novel thermal enhancement mechanism that results from including nano-scale particles in the cooling media environment. The contribution that hybrid-nanocoolants make towards machining performance is promising. However, the relationship between these coolants and surface roughness during turning of aluminum AA6061-T6 has not been studied so extensively. This study is aimed at studying the performance of oil-based hybrid nanocoolant on AA6061-T6 surface roughness in turning process. The optimum machining parameter of AA6061-T6 surface roughness was determined in turning process. This research will provide the expected results that can refine the principles in application of oil on the manufacture of machines for more precision as well as the quest for environmental considerations. The study adds to the existing literature by focusing on the little-known effect of nanocoolants on surface roughness in an effort to advance the practice of materials engineering and manufacturing technology. This study will be of great benefit to current industries because it is situated between the interdisciplinary areas of the material sciences, nanotechnology, and machinability as it proposes some innovative ways of machining that are both environmentally friendly and cost effective. The results obtained are not just broaden the knowledge on how nanocoolants are used, but also stimulate new efforts for optimal machining.