The disclosure herein describes throttling resynchronization operations in a cluster of distributed data stores based on I/O bandwidth limits. Resynchronization operations are added to a queue as they are received. A cluster resource manager accesses a resynchronization operation in the queue. A transient capacity value is determined and an available capacity value is obtained. A resynchronization limit of the cluster is identified, wherein the resynchronization limit indicates a maximum percentage of I/O bandwidth of the cluster that is for use by resynchronization operations. Based on a sum of the resynchronization capacity value and the transient capacity value being less than or equal to a product of the resynchronization limit and the available capacity value, the cluster resource manager initiates the accessed resynchronization operation on the cluster, whereby free space is maintained in the cluster for use by user operations.