Atomic layer deposition (ALD) was used to deposit TiO2 on Ni particles, and the catalytic activity of Ni for CO2 reforming of methane (CRM) was evaluated. In the presence of TiO2 islands on Ni surfaces, the onset temperature of the CRM reaction was lower than that of bare Ni. During the CRM reaction, carbon was deposited on the surface of bare Ni, which reduced the catalytic activity of the surface with time, and TiO2 islands were able to remove carbon deposits from the surface. When the Ni surface was completely covered with TiO2, the catalytic activity disappeared, demonstrating that tuning of the TiO2 coverage on Ni is important to maximize the activity of the CRM reaction.