Middlesbrough took the lead in controversial fashion in the 15th minute as Gary O'Neil raced clear before teeing up Scott McDonald, who had been in an offside position when the initial through-ball to O'Neil had been played.
The Eagles protested furiously at the decision to award the goal, but they drew level on the stroke of half-time as Alan Lee's cross was met by a powerful header from Alassane N'Diaye.
The home side came closest to grabbing a winner in the second-half but McDonald's saw a late effort saved by Palace goalkeeper Julian Speroni as Paul Hart's side held on for a point.
The draw kept Palace just a point adrift of safety, while Boro were left six points adrift of the play-off places after their fifth draw in six games.
Palace made a good start and almost went in front after four minutes when Lee got past David Wheater before firing in a shot which rebounded agonisingly off the post.
However the home side went in front when Palace tried to push up for offside but O'Neil played the ball into McDonald who made no mistake - much to the fury of the visitors.
The Eagles pressed for an equaliser and Darren Ambrose had a shot saved by Middlesbrough goalkeeper Brad Jones before N'Diaye fired over.
With half-time approaching Palace were back on level terms when Lee crossed for N'Diaye and he headed past Jones.
Middlesbrough came flying out the traps at the start of the second-half and Jonathan Franks' free-kick found Chris Killen but he glanced the header at Speroni.
That proved to be Killen's last meaningful act as he was replaced by Leroy Lita who was also off-target with a header.
The home side continued to push forward in search of the lead and Palace had Speroni to thank with 67 minutes gone when he did superbly to tip Barry Robson's 25-yard strike around the post.
Soon after Franks crossed for McDonald but he headed over from close range when he perhaps should have done better.
Palace were just about clinging on and Lita got into the left-hand side of the penalty area but he delayed his cutback too long and O'Neil was unable to make a meaningful connection.
Speroni is widely regarded as one of the best goalkeepers outside the Premier League and he showed why with three minutes remaining.
O'Neil got into space and set up McDonald who saw his volley superbly kept out by the Argentinian as Palace held on for what could prove to be a vital point.