Kummakivi () is a large balancing rock in Ruokolahti, Finland. The  long boulder lies on a convex bedrock surface with a very small footprint but so firmly that it cannot be rocked with human force.

Kummakivi has been protected since 1962. 

The boulder is located in a forest in the western part of the Ruokolahti municipality, near the border of Puumala.

References

Rock formations of Europe
Landforms of Finland