However, the City boss did confirm that John Stones would not be fit to face the newly-crowned Spanish champions.
Walker has been side-lined with an ankle knock since our quarter-final second leg tie away at Atletico Madrid last month.
But the England right back was back in training on Tuesday morning as City stepped up preparations ahead of flying out to Madrid.
And, addressing the media at Tuesday’s pre-match press conference, the City boss revealed Walker would continue to be carefully monitored between now and Wednesday before he makes a final decision on his availability.
“Kyle trained today and he will travel,” Guardiola confirmed.
“Tomorrow we will decide - he is three weeks without training but we are happy he is back. We will decide tomorrow.
"Yeah definitely (we have better options at right-back with Joao Cancelo also available after suspension).
“Joao is no doubt. He is really good. We will see with Kyle tomorrow how he is after treatment tonight and tomorrow. Then we will decide.”
However, the boss did confirm that Stones would not figure on Wednesday night.
The England centre half was forced to come off during last week’s dramatic 4-3 first leg win over the newly-crowned Spanish champions at the Etihad with a recurrence of a muscular issue.
And asked if Stones was fit to play, the boss responded: “No. He is not fit.”
Looking ahead to what promises to be another compelling evening following last week’s seven goal thriller, the boss said he was anticipating a similarly engrossing match.
While Real are seeking to claim what would be a 14th European crown, City are seeking to reach the final for a second successive year and to lift the trophy for the first time in our history.
“We are two good teams. We saw it a week ago when we played. They are champions of Spain. We are trying to be champions,” the City boss added.
“Both teams are good. I said a week ago we want to win and try and be in another final, for the second year in a row.
“(But there is) no guarantee the same guys will play the same way,. I don't know what will happen tomorrow. We will try and win the game with the best XI possible."