In this work gold and silver nanoparticles (AuNPs and AgNPs), functionalized with the n-conjugated dithiol, 9,9-didodecyl-2,7-bis-thiofluorene (FL) were prepared and their optical and electronic properties were investigated. The obtained nanoparticles showed low diameters and low size dispersion (4–5 nm), a very good solubility in organic solvents and can be easily deposited as stable film on several surfaces. The spectroscopic characterization revealed an absorption peak at about 525 nm for AuNPs and about 405 nm for AgNPs. The microscopy investigation showed uniform film of nanoparticles network. Furthermore the conductivity measurement showed ohmic behaviour for AuNPs that make these materials promising candidates for opto electronic devices.