Cardiff City missed a chance to return to the Championship play-off places as they were frustrated by struggling Millwall.
Joe Mason had a first-half shot cleared off the line before the Cardiff striker had a flicked header tipped over the bar by Millwall keeper Maik Taylor.
Millwall's Andy Keogh and Cardiff's Aron Gunnarsson found the net, but both efforts were ruled out.
James Henry missed a late open goal to clinch victory for the visitors.
Mackay furious with match officials
The point, however, aids the visitors' Championship survival bid as it nudges Kenny Jackett's men six points clear of the relegation places.
Cardiff's fourth successive draw was disappointing for boss Malky Mackay as the Bluebirds had dominated for long spells but their poor form of just two wins in 14 games continues.
The stalemate was the fifth time in the nine league games that Cardiff have failed to score as Mason, Stephen McPhail and Kenny Miller did not convert chances.
But, despite their woeful run, the Welsh side are still in touch of the Championship play-off places with six games remaining.
CARDIFF v MILLWALL FACTS
Cardiff are the Championship draw specialists with 16 this season
This was just Millwall's 11th point against a top-half club in 21 attempts this term
Millwall wore black armbands after former defender Barry Kitchener, their record appearance holder, died aged 64 after a short illness on Friday.
And it was the Londoners who had the best of the early chances as midfielder Henry fired over a 20-yard free-kick before smashing a shot wide.
McPhail tested Northern Ireland international Taylor from long range before a Mason strike was blocked on the line by Millwall defender Paul Robinson.
Gunnarsson then headed over for Cardiff while Liam Feeney blocked Liam Lawrence's effort.
Scotland striker Miller, without a goal in 15 games, shot at Taylor before the veteran stopper pushed Mason's header over the bar.
Gunnarsson nodded wide and Miller was again off target as Cardiff struggled to find a killer blow.
Kevin McNaughton saw his goal-bound drive well blocked by Josh Wright before Cardiff team-mate Miller was denied by Jack Smith.
In a rare foray into opposing territory, Henry blasted wide from 12 yards for Millwall even though the Cardiff net was empty.
Keogh thought he had got the winner for Millwall with 14 minutes remaining when he slotted home - but he was flagged offside.
The Republic of Ireland striker then brought a decent punched save from Cardiff keeper David Marshall when he pulled the trigger from six yards out.
Gunnarsson thought he had won the game for the hosts but referee Tony Bates had awarded Millwall a free-kick for a foul in the build-up as Cardiff were frustrated again.
Cardiff City 01 Marshall 02 McNaughton 03 Taylor 05 Hudson 25 Turner 07 Whittingham 13 Lawrence Booked 17 Gunnarsson 37 McPhail (Gestede - 63' ) 09 Miller (Earnshaw - 76' ) 20 Mason (Conway - 74' ) Substitutes 22 Heaton 11 Conway 23 Blake 10 Earnshaw 15 Gestede Millwall 39 Taylor 03 Craig 05 Robinson 21 Smith Booked 31 Lowry 14 Henry Booked 15 Feeney 26 Abdou 44 Wright (Ward - 90' ) 20 Keogh 37 Kane (Henderson - 59' Booked ) Substitutes 01 Forde 02 Dunne 18 Ward 08 Bouazza 07 Henderson