The new service will launch on Sunday, December 14.
The Virgin Trains service will stop at Shrewsbury, Wellington, Telford, Wolverhampton, Birmingham New Street, Birmingham International, Coventry and Rugby.
The Shropshire Star has campaigned for the direct link, organising a petition that was presented in the Commons.
The new service will be timetabled so that people will be able to take a day trip to London.
Monday to Saturday services will leave Shrewsbury at 6.39am and 3.24pm, arriving at 9.15am and 5.56pm.
The return services will leave London Euston at 10.23am and 6.23pm, arriving in Shrewsbury at 12.58pm and 8.55pm.
On Sunday, a single service will leave Shrewsbury at 3.20pm and return from London at 7pm.
Shrewsbury & Atcham MP Daniel Kawczynski, who has been campaigning for the rail link, reacted on Twitter this afternoon:
Telford & Wrekin Council leader Councillor Kuldip Sahota also expressed his delight at the news.
"Having a direct link is great news for Telford and Wrekin's residents and business community," he said.
"A major selling point of our Invest In Telford campaign is the fantastic transport links that we have but one obvious thing that we haven't currently got is a direct link by rail to the capital."
As part of the deal, Virgin said there would be "significant improvements" for customers with the introduction of free superfast WiFi, more seats and new services.
Lead Executive Phil Whittingham said: "It's an exciting time for everyone involved with Virgin Trains. With our extended franchise we are able to get back to doing what we do best, offering new journey opportunities whilst still delivering the same high standards of service to our customers.
"We have worked hard with our industry partners to gain the approval for these new services. Special thanks must go to the ORR, Network Rail and the Department for Transport. We thank them all for this big vote of confidence."
"We couldn't be more pleased and are really looking forward to working with all stakeholders to ensure they are a success and become a permanent fixture of the railway timetable."
A spokesman for Network Rail said: "Direct trains between London (and Blackpool) and Shrewsbury will be a valuable addition to the services which already connect both towns to the rest of the rail network. They will provide greater business and leisure opportunities and will support and develop local economic growth as a result of improved access to the capital.
"We have worked closely with Virgin Trains, the ORR and the wider industry to make this possible to help meet the demands of passengers and will continue to do so ahead of the first services being introduced in December 2014."