London Olympics chief Coe has joined ex-Liverpool chairman Sir Martin Broughton's bid.
Broughton, who announced his intention to buy Chelsea over the weekend, told the BBC "I am absolutely delighted to welcome Lord Coe to our bid. His reputation speaks for itself, and he will bring phenomenal insight, leadership, and sporting knowledge to Chelsea Football Club."
His group is expected to submit a bid in the next 48 hours.
Coe said he was "certain that Sir Martin is the right man to lead Chelsea Football Club into its next chapter" citing his "exceptional track record in British business".
Coe added "most importantly, like me, he is a lifelong Chelsea supporter and Shed End season ticket holder. I know that this bid is for the millions of Chelsea fans around the world. We love our club and will always put the fans first".
Broughton, 74, is a former British Airways chairman and now chairs private investment firm Sports Investment Partners. He was briefly Liverpool chairman in 2010.
Those close to the consortium declined to tell BBC Sport who was financing the bid or who else was involved.
Coe would take a seat on the Chelsea board if Broughton's bid is successful, according to the PA news agency.