To obtain a rubber composition which is made to keep the failure characteristic higher than those of the conventional reclaimed rubber and powdery rubber so that consequently the material recycling rate of waste rubber can be improved, and to provide a pneumatic tire.

The rubber composition contains the rubber powder obtained by pulverizing rubber chips. The rubber powder is manufactured by using a method for pulverizing rubber chips, which comprises: a coarse crushing step A of coarsely crushing rubber chips repeatedly once or more times to form into fine powder, a fine powder recovering step of collecting/recovering the fine powder obtained by coarsely crushing rubber chips; a secondary crushing step of furthermore crushing the recovered fine powder into particulate powder; a secondarily particulate powder recovering step of collecting/recovering the particulate powder crushed at the secondary crushing step; and a product step of screening the final particulate powder by using a filter having a predetermined mesh and withdrawing undersize powder. The coarse crushing step and the secondary crushing step are carried out by using a diamond-electrodeposited rotary drum and a diamond-electrodeposited fixed edge.

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