Mike Unsworth, who had been with the project since 2009, has taken a role at the Swansea Bay tidal lagoon project.
Stuart Grant, who has been working with Unsworth on the project since 2012, will become the new project director.
Navitus Bay has also announced the appointment of Mark Kempers as project implementation manager. He was an engineering manager at Eneco Wind between 2010 and 2013 and was most recently onstruction manager at Eneco's Luchterduinen project in the Netherlands.
Navitus Bay said it would also appoint a deputy project director responsible for finance in September.
Dutch utility Eneco is developing the project off the UK's south coast in partnership with EDF Energy. In May, MHI-Vestas was awarded a conditional agreement to supply the V164-8MW turbine to the development. Navitus Bay will be located 14 kilometres off the UK's south coast.
The project is awaiting a final planning decision by energy minister Amber Rudd, who has until 11 September to give the go-ahead.
It has been a difficult permitting process for the project, which has faced strong local opposition to the 121-turbine site.
Local MPs and pressure groups have campaigned fiercely against the plans, arguing it would spoil the area's tourism trade.
The Planning Inspectorate, the body responsible for handling infrastructure permitting applications, received a record number of "representations" from interested parties.
The examining authority refuses to categorise registrations as "for" or "against" a project, but the majority who register an interest, especially members of the public, commonly opppose an application.
Navitus Bay also submitted a 630MW Plan B "turbine area mitigation option" in its construction application to be considered alongside the larger plans.