Grayling, who commutes by train to Whitehall every day, said he did not see the case for different class compartments on shorter routes and added that passengers should no longer be “segregated”.
He told The Daily Telegraph that he expects to see fewer first class carriages on intercity services “over the next few years”.
The announcement comes as rail workers across the country continue to strike over proposed changes to their jobs.
Grayling's comments will doubtless be welcomed by punters making their way to The Open golf tournament at Royal Birkdale tomorrow, as Merseyrail confirmed its strike on Sunday would go ahead.
Drivers and guards are taking their leave as the long-running dispute over the role of the guard continues, although Merseyrail has said it will be running a service especially for The Open.
The transport secretary this week also agreed to talks with the Rail, Maritime Transport (RMT) union and train drivers' union Aslef, causing both to suspend planned summer strike action.
RMT announced earlier in the week that its Southern rail guard members would strike on Tuesday 1 August over the guard issue, while Aslef had announced fresh strike dates for August over a pay dispute.
But it isn't all sunny for Grayling, who sparked backlash yesterday as he announced the planned electrification of railways in Wales, the Midlands and the North had been scrapped.
Perhaps in an effort to distract from the rail dilemmas, the Department for Transport opened a public consultation into aviation strategy yesterday, with the government saying it wants to ensure safety and security, competitive markets and "help the aviation industry work for its customers".