Clarke, 32, will lead the Vikings in their first season back in the top flight following a six year absence, and he will be supported by fellow new signing Shaun Briscoe, who was named vice-captain.
Widnes coach Denis Betts said: “There were a number of candidates who could’ve done the job, and I’ve taken my time to come to a decision about who will captain the team.
“The reason we brought Jon into the organisation was for his experience and his leadership skills and both have shone through already in pre-season. Without taking anything away from the qualities that make him such a good person and player, I have every confidence the role will be a great progression for him.
“Between Shaun and Jon, it’s likely that either if not both of them will be on the field for most of the time during a game and it was important for me to feel confident in my decision making that I had selected the right people who could be trusted to fill the job descriptions. I’ve no doubt whatsoever that I have chosen the right men for the roles.”
Clarke, who spent 11 years at Warrington, is one of a raft of new faces at the Stobart Stadium as they move up from the Championship.
He said: “It’s a great honour to be chosen as captain of a club which has such a wealth of history behind it and I feel privileged to follow on from some of the big names that have captained this club in the past.
“When I was younger, I captained Great Britain academy and I also did it on a number of occasions at Warrington Wolves over the years, but to now have the full-time post as it were, is something I am really looking forward to both on and off the pitch.
“It’s a position I will take extremely seriously and I’ll give absolutely everything I’ve got to the role. The challenge of being a captain is being able to perform the leadership role alongside playing your own game just as well, so I’ll be hoping to lead by example in not just my words but also my actions as well.”