In this paper, the effect of multi-walled carbon nanotubes (MWCNTs) concentration on a TiO₂ based dye sensitized solar cell (DSSC) has been demonstrated along with the degradation study of the cell. Introducing MWCNTs into the semiconductor material reduces the resistance of the host material as well as enhances the thermal and electrical conductivity, mechanical strength, and flexibility. As the concentration of MWCNTs in TiO₂ is increased, the cell efficiency also increased gradually until it reached an optimum concentration of 0.015 wt. %. A further increase in MWCNT's concentration in TiO₂ leads to the negative effect of the DSSC's cell parameters by decreasing the short-circuit current and the fill factor, thus decreasing the overall cell efficiency. This result has been obtained by using a natural yellow dye extracted from turmeric (Curcuma longa). Without MWCNT incorporation, TiO₂ has the cell efficiency of 0.921%, but for the optimum concentration of MWCNT incorporation, TiO₂ has the maximum cell efficiency of 1.653%. Finally, the degradation study of the cell has been carried out for 360 hours.