The Gulf Railway, also known as the GCC Railway, is a proposed railway system to connect all six Gulf Cooperation Council member states in Eastern Arabia. The rail network will have a total length of 2,177 km. The project is estimated to cost US$250 billion. It was scheduled to be completed by 2030, the network is projected to serve 6 million passengers and transport 201 million tonnes of freight that year, increasing to 8 million passengers and 271 million tonnes by 2045.

Each of the six GCC member states is responsible for implementing the portion of the project that lies within its territory, and will construct its own railway lines and branches, stations and freight terminals. The cost will be shared by the six countries in proportion to the length of the rail network in each country. As a result, the United Arab Emirates and Saudi Arabia will spend the most on the project, followed by Oman, Qatar, Kuwait and Bahrain. The Saudi Railway Company will develop the network in Saudi Arabia, Etihad Rail in the UAE, Oman Rail in Oman, and Qatar Rail in Qatar.

The project has met hurdles on account of challenges with the financing of the project exacerbated by volatile oil prices, and lack of alignment of the interests of the six states involved. The expected date of completion of the project is uncertain, given the lack of clarity on the exact scale and operating model of the venture.

The Gulf Railway project was approved by GCC member states at the 30th GCC summit in Kuwait City in December 2009. Saudi Arabia was the only GCC country to have any railway infrastructure at the time the project was proposed. The original deadline to complete the project was 2018. This was postponed to 2021 at a meeting of GCC transport ministers in Riyadh in April 2016.

In November 2015, Saudi Railways Organization (SRO) President Mohamed Al Suwaiket stated that implementation of the GCC Railway had begun in Oman and the United Arab Emirates, and would begin in Saudi Arabia within 2 months. Qatar floated tenders for its portion of the Gulf Railway project in the summer of 2015, but later put the project on hold. In March 2016, Abdulla Al Subaie, managing director of Qatar Rail, stated that Qatar was ready to start work on the project but was waiting for other GCC countries to begin construction. In January 2016, Etihad Rail suspended the tendering process for Phase 2 of the UAE's railway project, which includes the UAE's portion of the Gulf Railway. UAE Minister for Infrastructure Development Abdullah Belhaif Al Nuaimi stated that the decision "was logical because you simply cannot build your part and wait for others to start".

In May 2016, Oman announced that it was putting the project on hold. Omani Minister of Transport Ahmed al-Futaisi said, "There was a challenge among countries in the pace at which the project was being implemented. Some countries started, but some others did not follow the design. So this was a challenge for Oman. Even if Oman finishes its part, it cannot connect because other countries have not started their work." He clarified that Oman "has not cancelled the project, only delayed it as other Persian Gulf countries have decided to stop work on the project". Oman subsequently focused on constructing its domestic rail network linking the ports of Salalah, Sohar and Duqm. Bahrain stated that it would not begin construction on its portion of the project linking with Saudi Arabia until 2023. The country intends to construct the link to Kuwait only after completing the Saudi link.

Futaisi and David Briginshaw, editor-in-chief of the International Railway Journal, have stated that the low price of oil and minerals that has resulted in budget deficits among GCC members is the primary reason hindering the project. Briginshaw said, "Low oil prices affect investment, and obviously [Oman's] project is designed to take minerals to the coast, so if there isn't demand it brings the whole project into question." The project was first conceived during an era of high oil prices. Unlike the EU, the GCC is not economically integrated, and states act independently and pursue their own policies sometimes creating competing economic agendas. Countries have chosen to give priority to their own domestic rail networks over the Gulf Railway, concerned that they may construct lines towards the border before their neighbour sufficiently completes work on their portion of the project. Other concerns hindering the project are visa issues for non-GCC nationals, illegal migration, smuggling, competing economic agendas and disagreements about where the lines should meet.

Helmut Scholze, partner at Roland Berger Middle East, believes the project is delayed due to the lack of clarity on when Saudi Arabia will build its portion of the network. Scholze states that without the Saudi portion, there was no point in UAE proceeding with it portion and even less incentive for Oman, as they would not gain access to Saudi Arabia (the region's largest market) and the other GCC countries. Scholze feels this has resulted in UAE and Oman focusing on constructing domestic rail networks to reduce road traffic and transport goods. Despite the delays, Scholze believes the project will be completed. Construction Week Online cited a rail industry source who also believed the project would be completed. However, the anonymous source felt that the "earliest [completion date] will be 2025 but, if you look at it realistically, the most likely completion date will be 2030".