Room temperature grinding of a mixture of calcium hydroxide and silicagel with different water contents was conducted in a planetary ball mill. Afwillite was synthesized mechanochemically by controlling the water weight rate at about 0.23-0.30. Two-hours grinding of the mixture containing with a water weight rate of more than 0.38 enabled the synthesis of other different types of calcium silicate hydrates. On the other hand, tobermorite was synthesized by three-hours grinding of the mixture having a Ca/Si molar ratio of about one and a water rate at about 0.8, while calcium silicate hydrates-(B) were mechanochemically synthesized by grinding during about 1.5 h. The water amount in the mixture plays a significant role to achieve the mechanochemical synthesis of these compounds.