Exhibit 21.1

Subsidiaries of Align Technology, Inc.

The registrant’s principal subsidiaries as of December 31, 2016, are as follows:

Entity

Align Tech De Costa Rica, Costa Rica

Align Technology, B.V., Netherlands

Aligntech de Mexico, S. de, Mexico

Align Technology, Inc., Delaware

Align Tech (Shanghai), China

Malocclusion C.V., Netherlands