Swinson said she hoped more companies would "give their employees a greater stake in their future and the success of their company".
The new FTSE-compliant index will help investors identify the 69 public companies listed on the London Stock Exchange with at least 3% of shares held by or for the benefit of ordinary staff.
Employee ownership means that workers have a voice as well as a stake in the success of their business and is promoted as a sustainable business model that helps drive staff commitment, productivity, resilience and innovation.
Swinson made the announcement yesterday at the launch of The Nuttall review of employee ownership: One year on report. The report measured the progress made by Government and the employee ownership sector against each of the 28 recommendations made in the first Nuttall report in October 2012.
"As we build a stronger economy, there has never been a more important time to promote successful ways of running a business," Swinson said. "Evidence shows that businesses that adopt the employee ownership model can be more profitable, create more jobs and are more resilient to economic shocks."
"The Employee Ownership Index will now mean investors can identify thriving employee ownership businesses and be part of their success. I hope more businesses recognise the value of this model and give their employees a greater stake in their future and the success of their company."
Nuttall said he was pleased with the progress made in a year, but there was "still more to do".
One of the recommendations taken on by the Government is the allocation of £50 million from 2014/15 to fund tax breaks for firms adopting employee ownership models.