Eight thousand extra seats are due to be added.
The project would take the stadium's total capacity to 40,000.
A 220-bedroom hotel and a multi-purpose event venue are planned for the site.
There are also proposals for a new Leicester City retail space, residential and commercial space, and multi-storey car parking facilities.
Leicester City Chairman, Aiyawatt Srivaddhanaprabha, said: “The unveiling of these plans represents a significant milestone in the long history of Leicester City Football Club, and one that we hope will continue to put our supporters and our community at the heart of its long-term future.
“Through the consultation with our fans, our local community, businesses and stakeholders, we hope to achieve something that we can all be proud of for years to come. It’s these conversations that will help us communicate our vision to the people at its heart and take onboard the views of our community to help shape it.
“While this vision is in its early stages, I know the prospect of additional capacity for more Leicester City supporters in King Power Stadium, has long been anticipated by us all, particularly after seven near sold-out Premier League seasons.
“The plans to build on the Club’s recent growth – with a stadium expansion as part of an exciting wider site development – is a wonderful demonstration of the shared ambition of both the Football Club and the city of Leicester. It is a project with the potential to generate enormous social value, starting with a substantial number of additional jobs for people in the region. We will be working with our partners and contractors to ensure this is a central consideration from construction through to long-term operation.”