CdSe/CdS quantum dots (QD) were synthesized and bioconjugated with Sambucus nigra agglutinin (SNA) lectin (Lec). Mannose triflate and cysteamine molecules (MTC) were also utilized to prepare MTC-QDs and MTC-QDs-Lec probes as well as Lec bound QDs. Afterwards; potential use of these nanoparticles as radiolabeled fluorescence nano-probes for the cell imaging studies has been investigated. Biological activities of I-125(-), I-125-MTC-QDs, MTC-QDs- Lec-I-125, QDs-Lec-I-125 and Lec-I-125 were examined on various cancer cell lines such as Caco-2, MCF-7 and A-549 in terms of cell incorporation. QDs-Lec-I-125 exhibited the highest cell incorporation on whole cell lines. In addition, the QDs-Lec-I-131, was used for in vivo imaging. The whole body distribution of the radiolabeled QDs on New Zealand rabbits and Balb C mice were examined by taking dynamic and static images. Radioactivity cleared from the kidneys and the bladder, while significant amount radioactivity was retained in the heart and liver within 24 h.