A run of eight frames in a row for the Londoner helped set up a clash with four-time world champion Ronnie O'Sullivan.
Hawkins won the final four frames of the morning session to level the tie at 12-12 and continued the pressure when he took the first four of the evening session.
Tonight's first frame proved key as Hawkins looked to have clinched it with a break of 66 only to miss a red to leave his opponent needing snookers.
Walden forced a re-spot on the black but could not complete the comeback as Hawkins took the lead in the contest for the first time.
The Chester cueist was back on the attack in the next frame but missed a simple red when on a break of 56, with the chance to draw level at his mercy.
That loss clearly affected Walden who looked mentally shattered.
Hawkins ground out the next two frames with breaks of 60 and 79 to go into the interval with a 16-12 lead and just needed one frame for victory.
The break clearly gave Walden the opportunity to regroup as the pots began to drop again and Hawkins began to feel the pressure with the winning line in sight.
On the crest of defeat, Walden slugged it out to take the next two frames to give himself a glimmer of hope.
But luck was not on his side in the 31st frame when his attempt to cannon into a pack of reds from the blue ended in misery when a red went in-off.
It set up Hawkins to set up a sizeable advantage in the frame and he held to complete victory.
Former world champion Terry Griffiths, who has been helping Hawkins on the mental side of his game, was first to embrace him as he came out of the arena.
Hawkins will need all the mental strength he can muster and to raise his game if he is to deny O'Sullivan a fifth world title.