Saranrom Park, formerly known as the Saranrom Royal Garden, is located opposite the eastern side of the Grand Palace. The area was initially created in 1866 by King Mongkut (King Rama IV) as a private garden within the grounds of Saranrom Palace, intended as a place of residence and retreat.

During the reign of King Chulalongkorn (King Rama V), the garden underwent a major transformation into a modern European-style botanical garden. The redesign was overseen by Henry Alabaster, a British diplomat and adviser, with construction supervised by Phraya Apirak Ratcha-uthayan (Chalerm Amatyakul). Saranrom became one of the first Western-style green spaces in Siam, bringing together rare plant species from various regions. Plans were also envisioned for a zoo to provide educational opportunities for the public. The garden thus combined the roles of a natural space, an academic resource, and a place of leisure for the royal court and elite of the time.

Under King Vajiravudh (King Rama VI), Saranrom Park was further used as a venue for winter festivals and public events. After the 1932 revolution that ended absolute monarchy, King Prajadhipok (King Rama VII) granted the park to the government. It became a central site for political activities, notably including the annual Constitution Day celebrations on 10 December and the first “Miss Siam” beauty contest, which later evolved into the Miss Thailand pageant.

The concept of a public park as a recreational space for citizens was still new to Siam, having been inspired by similar developments in major European cities. Although the royal court adopted this modern vision, Saranrom Park remained exclusive to the court and government officials for many years.

It was not until 1960 that the Cabinet formally transferred responsibility for the park to the Bangkok Metropolitan Administration, with a plan to convert it into a true public park. In 1981, the government decided to relocate the Rassadorn Club from the premises, compensating its members and allowing the park to become fully accessible to the general public.