Aiman al Qasmi, who had picked a silver in the 5km race, bettered his performance to claim the
gold in the 10km distance on Saturday.
And Khalid al Kulaibi, who had won the 5km gold, came second to make it an one-two to ensure sultanate's team title.
Qasmi had a time of 3hr:37min:20sec to win the title while Kulaibi timed 3:59:15s for the silver.
Aiman al Qasmi (second from right) receives the 10km trophy
Later, Taha al Kishry, the Oman Swimming Association (OSA) chairman and Arab Swimming Confederation chief and president of GCC Swimming Organising Committee, decorated the winners along with
Husain al Musallam, the FINA vice-presidentNidhal al Harassi received the silver medal on behalf of Khalid as the latter was too fatigued to attend the awards ceremony.
Adding to the joy of the senior team's exploits were Oman youth (15-17 years) swimmers, who picked the team gold in the 5km race. The team comprised Muhannad Auladthani, Shihab Alaa Deen and Bashar al Kulaibi.
Muhannad had also won an individual bronze medal in the 5km race.
The Oman delegation, which returned home on Monday with eight medals including five gold, two silver and one bronze, was headed by Mohammed al Hassani, OSA board member and accompanied by the team's chief coach, Serbia's Srdjan Filipovic.
The GCC championships in Kuwait was held along with the fourth Arab and ninth Asian open water championships.
Speaking on Oman's success, a delighted Kishry said, 'I would like to congratulate the boys and the coaching staff for the excellent results. Our swimmers demonstrated high standards on their way to gold medals.'
Coach Filipovic said, 'I am happy with the results at the championships, which was held along with Asian and Arab events.
'To have our swimmers compete against some of the best swimmers from Asia was an advantage as there were some big names from Japan and Kazakhstan.'
The former World Cup swimmer said, 'The experience of Khalid helped him and despite the long years he has put in the sport, his passion and commitment is praiseworthy.
'Muhannad has displayed good potential and has a bright future while Aiman has been consistent with his performances in Kuwait and controlled the 10km race for the gold.'