We present a thin film theory to unveil the interaction between the non-Newtonian effects and the Marangoni flow for a thermally actuated drop on a solid surface. Our numerical simulations with different equilibrium contact angles \((\theta _e)\) , shear-dependent viscosities (n), and dimensionless thermocapillary strengths \((\beta )\) reveal a nonlinear influence of the fluid rheology on Marangoni stress and disjoining pressure. For non-Newtonian droplets, we have identified three distinct spreading regimes. The behavior of the Marangoni film regime can be characterized by certain conditions. At lower values of \(\theta _e\) , higher values of \(\beta \) , and a specific range of n, the film exhibits a distinct linear drop shape. Additionally, for the shear-thickening drops, the thermocapillary time scale occurs early, and the advancing front becomes steeper, while drops with shear-thinning properties maintain a noticeable curvature for an extended period. On the other hand, when \(\theta _e\) is higher, and \((\beta \) , n) are lower, the droplets display a consistent shape and move at a uniform speed denoted as (U), which is identified as droplet regime. The droplets of this regime have a complex interaction of n and \(\beta \) , which leads to a considerable rise in U for shear-thinning fluids. Regardless of the regime, the shear-thinning droplet spreading is slower than that of Newtonian droplets, while the shear-thickening droplet spreading is faster in comparison. These findings can be employed in microfluidics to gain control over the spreading of non-isothermal biofluid droplets.