In the present work, surface treatment of surgical implant Titanium alloy with micro bioactive nanotube was experimented. Surface treatment of Ti-6Al-4V bio-implant carried out by giving alkali hydrothermal and heat treatment. The specimens were treated in 1M NaOH at 100, 150, 200°C for different holding time of 2 hr, 4 hr, 6hr, 12 hr, 24hr & 48 hr. The hydrogel layer generated during the alkali treatment was crystallized to sodium titanate (Na2Ti6O13) and resulted into the formation of nano sized tubes on heat treatment. X-ray Diffractrometry (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) revealed the different phases and surface morphology of these nanorods. The biocompatibility test done using Simulate Body Fluid (SBF) showed that the Hydroxyapatite (HAp) was well formed at the sodium titanate nanotube layer generated on the Ti-6Al-4V specimen. The best condition for this increase in surface biocompatibility was optimized to 6 hours hydrothermal treatment under 200°C using 1 M NaOH followed by 1 hour heat treatment at 600°C.