April 9 Kristin Dolan, a Cablevision executive who is also married to Chief Executive Officer James Dolan, will become chief operating officer, the cable TV provider said on Wednesday.
The company added that James Dolan will hand his title as president to veteran company executive Brian Sweeney, while Dolan will remain CEO.
Kristin Dolan previously served as president of Optimum Services and has been at the company for 24 years. She and James Dolan announced a trial separation last year, although they are still married.
The company declined to comment on the Dolans' personal relationship.
Sweeney, 49, will be promoted from his current post of senior executive vice president, strategy and chief of staff. He has held many roles at the company over the past 20 years.
Cablevision has not had a chief operating officer since Tom Rutledge left in 2011. He later became chief executive of Charter Communications.
Both Kristin Dolan and Sweeney are on Cablevision's board of directors.
In February, Cablevision said it lost fewer video subscribers than expected in the fourth quarter and said the company expects growth in cash flow in 2014.
Cablevision, with about 3 million subscribers has a foothold in markets such as Long Island in New York and New Jersey.
Shares closed 4 cents lower by 0.22 percent at $17.40 on Wednesday. (Reporting by Liana B. Baker; Editing by David Gregorio)