Brain tumor is insidious complication which is difficult to treat because of the poor uptake of many potentially useful antitumor drugs through the blood-brain barrier (BBB). Present study was aimed for developing and exploring the use of thiamine conjugated poly(propylene imine) (PPI) dendrimers for increased delivery of paclitaxel (PTX) across the BBB. PTX loaded thiamine conjugated PPI dendrimers (PTX-Tm-PPI) shown increased drug loading and reduced hemolytic toxicity with suitability for prolonged delivery of PTX during in vitro release. Ex vivo cytotoxicity studies of free PTX, PTX-PPI and PTX-Tm-PPI dendrimers over IMR-32 human neuroblastoma cell line revealed higher potential of PTX-Tm-PPI nanoconjugate to retard tumor cell viability as compared to plain PTX or PTX-PPI. In vivo pharmacokinetics studies revealed significant (p < 0.05) slow clearance of PTX from the body via Tm-PPI nanoconjugate. Biodistribution studies confirmed about the targeting efficiency and higher biodistribution of Tm-PPI conjugates into the brain. The results concluded that the developed nanoconjugate has potential to deliver significantly higher amount of drug to brain tumor for improved therapeutic outcome.