<p>The near-equiatomic nickel-titanium shape memory alloy has become a competitive bioimplant material due to its exclusive shape memory and superelastic behavior. However, its poor mechanical properties compared to other implant materials greatly confine its application in biomedical industries. Hence, the main objective of this research is to investigate the effect of various solution and ageing treatments on microstructural evolution and mechanical properties of biomedical superelastic NiTi shape memory alloy. The Ti₂Ni and Ni₃Ti precipitates were formed in as-furnace cooled, as-water quenched, and as-ice quenched NiTi alloys, whereas the monoclinic B19'-NiTi martensite phase was observed along with Ti₂Ni and Ni₃Ti precipitates in as-liquid nitrogen quenched NiTi alloy. The isothermal ageing treatment results in the formation of Ni₄Ti₃ precipitates irrespective of quenching media. Among all the solution-treated and isothermally aged NiTi alloys, the liquid nitrogen-quenched NiTi alloy exhibited better mechanical performance for an ageing period of 10&#xa0;h. The liquid nitrogen-quenched isothermally-aged NiTi alloy exhibited maximum hardness and ultimate tensile strength were recorded as 471.66 Hv and 1129&#xa0;MPa, surpassing the as-furnace cooled NiTi alloy by more than 53.80% and 3.78% respectively. The ductile, cleavage fracture and quasi-cleavage fracture patterns were observed during tensile fractography analysis.</p>