To provide a shoe sole which is excellent in strength and durability in spite of its light weight.

This shoe sole 1 comprises a mold of crosslinked rubber without including bubbles, and its specific gravity is 0.900 or more and 1.100 or less. This shoe sole 1 contains silica of a primary grain diameter of 5 nm or more and 30 nm or less by 10 parts or more and 40 parts or less to 100 parts of base rubber 100. In this shoe sole 1, blended quantity of softening agent is 3 parts or less to 100 parts of rubber. The base rubber contains vinyl cis- polybutadiene rubber of 5 mass % or more and 100 mass % or less. Instead of vinyl cis-polybutadiene rubber, (A) high cis-polybutadiene rubber as first rubber, and (B) one or two sorts selected among high styrene rubber and 1,2-butadiene rubber as second rubber may be used.