Andy Symonds and Cooper Vuna both went over for the hosts, either side of Neil de Kock's try for the league leaders.
Two tries from Ashton and Samuela Vunisa gave the visitors a 29-14 lead at the break.
Ashton and Ben Ransom touched down after half-time before Vuna claimed his second of the match.
As well as playing in the final of European rugby's elite competition against French Top 14 side Racing 92 in Lyon on 14 May, Saracens must now also prepare for a Premiership semi-final against Leicester Tigers.
Worcester, who have finished 10th in the table, are to follow in Sarries' footsteps by moving from playing on grass to an artificial pitch from the start of next season.
Saracens director of rugby Mark McCall:
"We've led the Premiership for three out of the last four seasons. To get 80 points, without our internationals (who were) away for such a long period is a tremendous achievement, but the best is yet to come as we have a young squad.
"Last week we played poorly in the first half against Newcastle but we were impressive today."
Worcester Warriors director of rugby Dean Ryan:
"They are an outstanding side - we struggled with their power and we need to increase depth in our squad if we are going to improve.
"For the 15 minutes before half-time we were nowhere near, we struggled with our kicking game and kept feeding Alex Goode and we never laid a hand on him.
"It's a stark reminder of the top and where we are. We have to bring more power into our squad."
Warriors: Pennell; Heem, Symons, Mills, Vuna; Heathcote, Baldwin; Leleimalefaga, Annett, Schonert, O'Callaghan, Sanderson, Betty, Kirwan, Dowson (capt).
Replacements: Bregvadze, Bower, Johnston, Hewitt, Cox, Mulchrone, Lamb, Grove.
Saracens: Goode; Ashton, Bosch, Tompkins, Wyles; Hodgson (capt), de Kock; Barrington, George, Du Plessis, Kruis, Hamilton, Wray, Brown, Vunisa.
Replacements: Saunders, Lamositele, Figallo, Smith, Fraser, Spencer, Streather, Ransom.

Ban Ki-moon said he witnessed a looting incident in Les Cayes, where he promised more aid to Haiti. He also urged countries to donate more.
Officials says more than 1.4 million people urgently need humanitarian help.
There are also fears of a cholera outbreak, with spikes in cases and deaths reported in the south west.
The waterborne disease reached the island via Nepalese UN troops after the deadly earthquake in 2010, causing the deaths of nearly 10,000 people.
Tensions have been high as help has yet to reach many families whose crops and water supplies have been destroyed.
Haitian police and UN peacekeepers used tear gas to disperse a group of 100 residents who attacked humanitarian convoys in Les Cayes on Saturday.
"We understand the impatience and the anger of the population who are waiting for emergency relief. We are doing all we can to facilitate the arrival of the assistance soon as possible," Mr Ban said.
He flew over areas hit by the hurricane alongside Prime Minister Enex Jean-Charles.
"I was very, very sad when we saw the complete devastation. But people the world over stand with you," the UN chief added.
"We are going to mobilize as many resources and as much medical support as we can to first of all stop the cholera epidemic and second support the families of the victims."
Some 120,000 homes were either damaged or destroyed when Category Four Hurricane Matthew swept through on 4 October with winds of 145mph (230km/h).
Mr Ban visited a shelter in Les Cayes and told the displaced "kembe fem" in Creole, meaning "hang in there".
In the town, one of the worst affected by Matthew, the streets have been cleaned and business have reopened.
But power, transport and communications links are still difficult in other areas.
Last week, Mr Ban called for a "massive response" to help the country, the poorest in the Americas.
The UN launched an emergency appeal for nearly $120m (Â£97m) in aid, but just a fraction of it has been raised.
Mr Ban acknowledged there was aid "fatigue", but urged countries to help Haiti.
Chris Ashton scored a hat-trick as Saracens prepared for next weekend's European Champions Cup final by comfortably beating Worcester.
[NEXT_CONCEPT]
Angry Haitians looted aid trucks as the UN secretary general visited parts of the country hit by Hurricane Matthew, which killed 900 people.