Neil spent four years as a player with the Tykes, getting his first taste of English football there after moving from Scotland.
At the half-way stage of the season, North End are in eighth place and only two points behind Aston Villa who occupy the final play-off slot.
The 1-1 draw with Nottingham Forest at Deepdale on Saturday extended their unbeaten run to seven games - one they will be looking to stretch further in South Yorkshire on Boxing Day.
Neil said: "It will be tough at Barnsley.
"I know they have been struggling of late but they are a competitive team and we had a real difficult game against them here earlier in the season.
"We are in good form, we are unbeaten in seven and playing well.
"Teams are finding it difficult to beat us and if we can add more goals to our game, that is a key thing.
"If we can improve that side of our game, defensively we have been relatively solid all season.
"The lads are confident, we had some really good performances against Forest.
"We have been focused on chasing the teams above us, we want try and break into that top six because once you are there teams are chasing you rather than the other way round.
"That has been a real focus, we are only two points outside the top six.
"Our aim was to be up there in contention at the turn of the year."
While Neil will find the surroundings at Oakwell familiar, so will North End midfielder Ben Pearson who had two loan spells there from Manchester United.
The performance Pearson put in against Nottingham Forest will be one Neil hopes can be repeated on Boxing Day.
"I thought Ben was sensational on Saturday, in terms of sitting midfield player you will struggle to see a better performance than that.
"He was fantastic. For me, Ben is the perfect sitting midfield player.
"When you need that anger, determination and hunger to get the ball back, he does that.
"But he also has a cool head to pick a pass with quality.
"Listen, Ben is a top, top player."