Systematic investigations of crystal structure, electrical conductivity and photoconductivity have been carried out on the complete series of TlGa(SxSe1-x)(2) solid solutions. X-ray diffraction (XRD) analyses together with TREOR90 computer program have revealed that this compound shows different structural modifications at each composition. The possible charge transfer mechanisms have been investigated by performing temperature dependent electrical conductivity measurements in the temperature range of 100-400 K for different values of x. Information about the band gap of these composite solution have been investigated by means of spectral distribution of photocurrent as a function of x. Temperature dependent photoconductivity behaviour and characteristics of the recombination centers have also been investigated by measuring photocurrent at various illumination intensities and applied electric fields in the studied temperature range. (c) 2006 Elsevier B.V. All rights reserved.