For Dropbox Business users, you can have both a personal Dropbox and a work Dropbox on any computer or mobile device, as well as on the web.
Connecting your Dropbox accounts does not give your admin visibility or control over personal data in your personal Dropbox, other than whatever control or visibility your admin may already have over company-managed devices. As always, it's a good idea for you to check with your admin about policies and procedures when it comes to putting personal data on company-managed devices.
Admins for Dropbox Business teams can view any groups you are a part of, but again, they do not have visibility or control over personal data in your personal Dropbox, other than whatever control or visibility they may already have over company-managed devices.
Keep in mind that your admin can restrict you from linking both Dropbox accounts to a single computer at the same time. However, you’ll still be able to access both your personal Dropbox and work Dropbox through the website and your mobile devices.
If you're a member of a Dropbox Business team, and you have connected your personal and work Dropbox accounts, your team admin can sign in to your Business account using "Sign in as user." However, this feature does not allow team admins to access your personal account in any way. Only your Business account is accessible to admins.