The regulator said the investigation followed complaints from customers and would focus on the fairness of the company's terms and conditions, specifically its charges for ending a contract early.
It will include circumstances when a customer has to terminate a contract because they are moving house.
All providers must ensure that their conditions or procedures for customers wanting to terminate a contract do not act as a disincentive for switching provider.
Complaints have surfaced on various forums from Virgin Media customers who have been charged into the hundreds of pounds in early disconnection fees after signing up to set term contracts but finding they needed to move house part way through the agreement.
Virgin runs its own cable network, which means that customers can only take their contracted service with them if their new house is also connected.
Virgin Media's website says the early disconnection fee is charged depending on what services a customer has and how much of the minimum period remains for each service.
For example, a customer who has the company's current Full House bundle with five months remaining on the contract would be charged a total early disconnection fee of £217.20.
A Virgin Media spokesman said: "We note Ofcom's investigation into early termination charges and will work with them during the course of their inquiry."