The system operates over 1,435 mm (4 ft 8+1⁄2 in) standard gauge track, using 750 V DC overhead power supply.

When Tuen Mun was developed in the 1970s, the Hong Kong government set aside space for the laying of rail tracks.

In 1982, Hong Kong Tramways showed interest in building the system and running double-decker trams on it, before abandoning the project after negotiations over land premiums for related property development failed.

[5][6] The KCRC announced they would build the system in 1984 to a budget of $1.5 billion, after investigating ways to improve commercial viability.

By that time, Kowloon Motor Bus (KMB) had developed its own network in Tuen Mun and Yuen Long, and there were about 10 routes serving within the districts internally, most of them profitable.

[8][9] The system consisted of two large and three small loops serving most of the public housing estates in northern Tuen Mun.

Seventy single-deck LRVs were manufactured in Melbourne and Brisbane, Australia by Comeng, to be shipped to Hong Kong for the seven LRT routes in the system.

The eastern extension branches off the main line south of Siu Hong stop and crosses the river that runs through Tuen Mun immediately with a flyover.

A short spur was also built from the extension to another terminus at Sam Shing Estate, located near Castle Peak Bay.

Tin Shui Wai was originally an area with numerous fish ponds, but was developed as a residential new town in the early 1990s.

The system remained essentially unchanged until the completion of the West Rail (now Tuen Ma line) in December 2003.

The KCRC designed most railway stations in the LRT area to interchange with the new West Rail line.

For this purpose, an interchange discount system was launched with the introduction of the West Rail line system, meaning that passengers would pay no more (and in some cases less) to travel on West Rail line instead of the LRT for the main part of their journey.

Phase IV LRVs were manufactured by United Group[15] and CSR and entered service in December 2009.

The newest Phase V LRVs were manufactured by CRRC Nanjing Puzhen and entered service on 17 November 2020.

Withdrawals began on 28 August 2022, with the first two Phase II LRVs (1079 and 1204) removed from Tuen Mun Depot and sent to the scrapyard.

[18][19] One of the retired cars now survives at the Ying Wa College and Primary School, transformed into a classroom.

There are six fare zones – 1, 2, 3, 4, 5 and 5A – for passengers purchasing single-ride tickets in Light Rail stops.

Passengers may enter the system after scanning their Octopus card at an orange 'Entry Processor' reader.

If a person exits the same platform with the same card within 5 minutes, the fare deducted will be fully refunded.

Like enquiry processors found in other places, passengers can check the balance on their card, along with the 10 most recent Octopus transactions.

If a Personalised Octopus card is used, the number of Light Rail credits accumulated is also shown.

Passengers using Personalised Octopus cards are able to participate in the Light Rail Bonus Scheme.