Siam Navy

The club was formed on 10 January 1956 as the Royal Thai Navy Football Club and currently plays under the name of Navy Football Club, locally known as Rajnavy. The club has also played under the names of Rajnavi and Rajnavy Rayong, Rayong being the town they played in and the main base of the Navy in general.

Since the inception of the Thai League in 1996 the club played under the name of the Royal Thai Navy up until 2009, when all teams in Thailand had to become public limited companies. With this, many teams changed names and formed closer links with the communities they were based in. In this case the Navy became known as Rajnavy Rayong. Rajnavy being the local Thai name for the Navy. In 2011, and with a dispute as to the ownership of the club, the club moved from their Rayong home and into the Chonburi province where they ground share with Pattaya United – another club playing outside of their original home town – albeit against league rules, where two sides in the PLT cannot ground share.

In 2009, when Thai football was becoming increasingly popular with all professional football teams told to properly register and become a company limited, the situation was almost to the point where anyone could register this football club for an ownership. At this point, Rayong Thai Premier took the ownership and renamed the club to Rajnavy Rayong. However, two seasons after that, the Royal Thai Navy decided to bring the team back under control and renamed it to Siam Navy. Thereafter, the football club moved from Rayong to Sattahip, Chonburi.

At the start of the 2011 league campaign, with the Navy in a bit of turmoil after the dispute of the owner of the club, they proceeded to get it wrong on the field as well. Their opening game of the season against Sisaket, was awarded 2–0 to Sisaket after an original 1–1 draw due to Siam Navy playing an ineligible player. To make things worse, the club knew the player in question couldn't play, but carried on hoping to get away with any sanctions – especially since the league is normally lax in the rules.

In 2006 the club won the opening season Queen's Cup tournament. A tournament that is not mandatory but nonetheless a big part of the Thai football calendar at the time. They defeated Krung Thai Bank in the final after getting past Bangkok Bank at the semi-final stage.

The club has somewhat become known as a yo-yo club in the Thai football scene, being relegated and promoted from/to the top flight on four occasions. Although on each occasion they were promoted they were not as champions.

In 2022, Navy competed in the Thai League 3 for the 2022–23 season. It is their 26th season in the professional league. The club started the season with a 1–2 away defeat to Chanthaburi and they ended the season with a 1–1 home draw with Chanthaburi. The club has finished 11th place in the league of the Eastern region. In addition, in the 2022–23 Thai FA Cup Navy was defeated 2–4 by Amnat Charoen City in the second round, causing them to be eliminated and in the 2022–23 Thai League Cup Navy was penalty shoot-out defeated 3–5 by Uthai Thani in the qualification play-off round, causing them to be eliminated too.