Abstract Solution processable small molecules are an alternative to conjugated polymers in organic photovoltaics and have recently been in the focus of intense research. In this work, organic–inorganic hybrid solar cells with active layers consisting of the solution-processable small-molecule p-DTS(FBTTh 2 ) 2 and copper indium sulfide nanoparticles are presented. The copper indium sulfide nanoparticles are formed in situ directly in the small molecule matrix from metal xanthate precursors. The prepared nanocomposite small molecule/copper indium sulfide films are very smooth, highlighting the good compatibility of p-DTS(FBTTh 2 ) 2 with the in situ preparation of metal sulfide nanoparticles. The formed nanoparticles have diameters of about 3 nm. Hybrid solar cells, exhibiting power conversion efficiencies of 1.3%, are characterized by IV curves, EQE spectra and electron microscopy.