The 24-year-old played an integral part in Wales' glorious RBS 6 Nations campaign, taking over the captaincy when Gareth Thomas was injured in Paris and inspiring the team to a stunning victory.
Lions head coach Sir Clive Woodward was impressed by the way Owen then led Wales to a record victory over Scotland in Edinburgh and the Grand Slam-clinching triumph over Ireland at the Millennium Stadium.
"He had a fantastic Six Nations and reflects why Wales were successful,' Woodward said.
"I spoke to him on Tuesday night and it took him less than 0.1 seconds to accept that role.
"It is a huge honour to captain the Lions at any time, but this will be a very special occasion for Michael to captain the Lions in this game in Cardiff.
"I have no doubt he will acquit himself well."
Immediately after speaking to Woodward, Owen told his wife, Lucy, and swore her to secrecy. But anyone who saw him around the Lions camp on Wednesday morning could have hazarded a guess.
"Clive told me and I haven't stopped smiling since," Owen said.
"The Lions don't get to play at home very often and playing in the Millennium Stadium it will be brilliant.
"I can't afford to think about the history of it at the moment because it would be quite overwhelming. I have to put that to the back of my mind and try and treat it as a normal game.
"When people talk about what it will be like, with the crowd, it is fantastic but I have got to distance myself from the emotional side.
"The experience of the Six Nations will help me. There are so many people in the squad who could take on the role and I was lucky enough to be given the opportunity.
"I'll give it everything I've got and hopefully will do a good job."