Targeted drug delivery enhances drug efficiency and selectivity without affecting normal cells. Luminescent nanoparticles can be used for tumor imaging as well as selective tumor targeting for drug delivery. In this research, LaVO4:Eu3+ was synthesized, the luminescent nanocrystal was coated by surface polymerization of levodopa in the presence of Paclitaxel (PTX), and then NL2 peptide was coupled on the surface of polymer‐coated luminescent nanoparticles. Next, the capability of the modified drug was examined by in vitro and in vivo experiments. MTT assay on SK‐BR‐3 cell line (as breast cancer cells) and fluorescent microscopy results indicate that this modification decreases significantly drug toxicity and increases its selectivity. In addition, in vivo experiments confirm more capability of the NL2‐functionalized nanocomposite for reducing tumor size, drug distribution in the body, and more aggregation of PTX in tumor tissue. Overall, it is concluded that tumor imaging is possible using luminescent LaVO4:Eu3+ core and NL2 peptide increases significantly the specificity of PTX in combination with a functionalized luminescent polymeric carrier.