Whilst there is some debate, it is recorded that a mansion house has existed on this site since 1561, although it is known that the first Tylney Hall was built about 1700. That building was demolished by William Pole-Long-Wellesley, later the 5th Earl of Mornington who had inherited it, either for the price of the materials, or in order to sell the timber on the estate. A possible explanation is that by the terms of the Trust, timber could not be felled within sight of the house, so he pulled it down. Timber, particularly in Hampshire, relatively close to the naval Dockyards at Portsmouth, was then at a premium.

The Hall as it now stands was built at the end of the 19th century under the supervision of Sir Lionel Phillips. It has served in a variety of roles since, including a Hospital and an ASC base for mules in the First World War and in the Second World War, the headquarters of Clan Line Steamers Ltd., the then famous steamship company owned by Lord Rotherwick, who had bought the Hall in 1919. It became a school in 1948, until it closed in 1984. It then re-opened as a hotel, after extensive refurbishment, the following year. It is now one of a string of luxury hotels owned by Elite Hotels.