The colony landed outside the clothing store Topshop on Victoria Street, momentarily trapping at least one female shopper who froze on the spot as the bees flew around her.
Much of the hive clung to the window, while another portion spilled onto the sidewalk.
The Guardian newspaper said Tony Mann, a manager from the nearby John Lewis department store, arrived at the scene wearing protective clothing and a netted hat and said he would organize the task of smoking the bees into a box for a safe removal.
The paper said the colony was later moved by local beekeepers across the road to the roof of Westminster cathedral.
It's common for honeybees to look for a new hive in the spring, but it's not clear where these honeybees came from.