The condos are on leased land. The land owner owns two condo units in the complex.
The land owner has been elected to serve on the Home Owners Board of Directors, HOA.
Where is the conflict of interest?
There is opportunity for undue interest / influence by the Land Owner on possible community issues.
How best to handle this?

Thanks

Why do you think so? If he is an owner, that should entitle to serve on the board. It would be up to the other board members to see that he doesn't unduly influence decisions that can affect his lease holding.