Liam Rosenior was sent off in the second period for two bookable offences as Steve Coppell's high-fliers were made to sweat for their point against resolute Palace.
Reading dominated the opening exchanges, but it was Palace who came closest to opening the scoring in the 21st minute when keeper Marcus Hahnemann denied Anthony Stokes fully capitalising on Michael Duberry's mistake with a fine save.
Referee Andy D'Urso waved away strong claims for a Reading penalty in the 27th minute after Jose Fonte felled Dave Kitson in the box before Eagles youngster Nathanial Clyne tested the Royals' American shot-stopper with a 30-yard half-volley.
Neil Danns blazed wildly over the bar in the 38th minute, while Shefki Kuqi and Stokes missed decent chances for the home side to take a half-time lead.
Palace started the second period in the same style they ended the first, Victor Moses smashing an angled half-volley straight at Hahnemann two minutes into the second period as Palace continued to dominate proceedings.
On-loan Dave Kitson was inches away from giving Reading a 65th-minute lead with a superb curling effort from the edge of the box before Rosenior was given his marching orders after a lunge on Moses resulted in his second yellow of the afternoon.
And the sending-off breathed life into Palace with Kuqi and Danns missing half-chances before the big Finn saw his deft effort from Moses' low cross trickle just wide as the clash ended goalless, denting the Royals' automatic promotion hopes in Coppell's 1001st game as a manager.