The influence of lead(II) sulphide (PbS) on the formation and superconducting behaviour of (Tl1-xPbx)Sr2CaCu2O7 (Tl-1212) phase for x = 0.1, 0.3, 0.4. 0.5, 0.7 and 0.8 was investigated. The samples were prepared using the solid-state reaction method. Lead(II) sulphide was used as the source for Pb. The XRD patterns showed majority Tl-1212 phase along with other impurity phases including PbSO3. The highest onset transition temperature, Tc-onset = 104 K was observed in the x = 0.8 sample. This is higher than (Tl0.4Pb0.6)Sr2CaCu2O7 prepared using PbO where Tc-onset = 97 K. The average nanoscale crystalline grain size calculated based on the Scherrer-Warren equation was in the range of 22-101 nm. AC susceptibility measurements showed that the transition temperature, Tc' increased as PbS content was increased. This works showed that diamagnetic PbS enhanced the electrical properties of individual superconducting grains for Tl-1212 phase. The effectiveness of PbS versus PbO on the Tl-1212 superconductor is also discussed in this paper.