Aim: This study was carried out to evaluate the effect of mechanical fatigue and chemical aging protocols on color stability and translucency of two types of dental resin composite material; nanohybrid and nanofilled. Method: Twenty disc-shaped specimens were prepared from each composite type. The 20 specimens were further equally divided into two groups according to aging procedure. Mechanically aged and chemically aged nanohybrid groups were designated with Gp 1A and Gp 2A, respectively. While nanofilled specimens were designated with Gp 1B and Gp 2B for the same aging treatments, respectively. Baseline readings for color and translucency were recorded before any aging treatment. The specimens were subjected to mechanical fatigue and chemical aging treatments. Using Reflective spectrophotometer, the change in color (Δ E) and translucency parameter (Δ TP) were measured. Results: Δ E of Gp 1B was significantly higher than of Gp 1A, while chemical aging protocol resulted in insignificant difference in Δ E of Gps 2A &2B. There was a significant increase in translucency after both aging protocols. Translucency of groups Gps 1A & 1B increased with insignificant difference between them. However, Gp 2A showed a significant increase in translucency than did Gp 2B. Conclusions: With the limitations of this study, mechanical fatigue aging could produce a significant higher change in color of dental resin composite than chemical aging protocol. Mechanical fatigue aging protocol could produce similar effects in translucency of both types of composite. while chemical aging protocol caused a significant difference in translucency of the nanohybrid composite material.