Pardew's time at St James' Park appears limited in the wake of Saturday's 4-0 drubbing at Southampton, that left the club winless and bottom of the Premier League table after four matches.
Newcastle's loss to Southampton - their 15th Premier League defeat from 23 games since the start of the year - has only increased the pressure on Pardew, who was subject to an online campaign calling for his sacking.
Hull City tactician Steve Bruce has already been mentioned as a possible successor should Newcastle owner Mike Ashley part ways with Pardew.
However, former Newcastle boss Souness, who spent two-and-a-half seasons at the club between 2004-06, said pressure is part and parcel of job.
"Results are everything. It used to be you got half a season or a full season if you were not winning but now you get six matches. If you are in such a job then you know that is the case," Souness told Sky Sports News.
"Newcastle is a big club with very passionate supporters who can get very, very frustrated at times and can be very quick to show their emotions, but that's the price on the ticket if you want to manage a club like Newcastle.
"You know that if it does go wrong your head will be on the block. That's where he finds himself unfortunately.
"I've had banners [demanding my sacking] like that. That's part of the deal. I've been fortunate to manage some very big football clubs and that's the price on the ticket.
Souness added: "You have to be thick-skinned, have the support of the people around you and hope you have the players still with you.
"If that's all in place and the board is still with him then he might get through it, but it's a tough time for him. Anyone who's been a manager would only have sympathy at this time."
