Newcastle remain joint bottom of the table alongside promoted Burnley after Monday's 1-0 defeat at Stoke City left the club still searching for their first win of the season.
The loss - Newcastle's third in six matches - only increased the pressure on manager Pardew, who was jeered by travelling fans at the Britannia Stadium.
Pardew admitted post-game that a "big question mark" hangs over his future amid growing calls for his sacking.
Former Manchester United defender Neville said he believes Newcastle's transfer policy, which centres around signing players from outside England's top flight, has proved detrimental in 2014-15.
Of the six players brought into the first team squad this season, only one has Premier League experience - Jack Colback, who arrived from rivals Sunderland.
Ayoze Perez (Tenerife), Siem de Jong (Ajax), Remy Cabella (Montpellier), Emmanuel Riviere (Monaco) and Daryl Janmaat (Feyenoord) were all signed from abroad.
"It must be really difficult for him and he's hurting badly," Neville told Sky Sports on Monday.
"As much as the Newcastle fans want him out, they must see a man there who is doing his absolute very best and is trying as hard as he can.
"He is trying to work with a team with a lot of new players to integrate into the squad and it isn't quite working for him in the attacking third in particular.
"Newcastle have had a recruitment policy where they have brought in players, some of them half well-known and some of them not really well-known, particularly from France and they've done OK with that.
"But if ever Alan Pardew needed a certainty this summer it was people who are tried and trusted in the Premier League and people he knew would hit the ground running for him. They have brought in Riviere and Cabella, who have not adapted to this league.
"There is a higher risk attached to those types of signings than there is with players who have already been here, settled and done it over a period of one to three years.
"I'm not sure if Alan Pardew is in control of the signings at the club, but I would have to say that if I was him this summer, knowing there was pressure at the end of last season, you wanted tried and trusted – and he hasn't got that."
