Dominic Poleon's first half double was cancelled out in the second half by Jason Holt and Jamie Murphy's goals.
Poleon, who spent time on loan with the Blades earlier in his career, gave Latics the lead on 23 minutes after a well-taken finish.
The forward struck a goal of the season contender just before the half time break but goals in the second half for Sheffield United meant the points were shared at SportsDirect.com Park.
Latics started the game brightly putting pressure on the Blades defence from the first whistle.
Liam Kelly was the first man to go close for Latics as he shot from 25 yards and Sheffield United goalkeeper Mark Howard was just behind it to tip it away.
Poleon was proving a bright spark in the Latics attack as he took on his defender two minutes later but after going down in the penalty area, the referee waved away his penalty protests.
Rhys Turner and Danny Philliskirk were threatening with the ball in attack as they applied pressure to the Blades' defence.
Latics had to wary of the counter attack as they went in search of the opening goal but Joel Coleman proved to be a hard nut to crack as he denied Marc McNulty from inside his six yard box.
Midway through the half, Athletic took the lead courtesy of Poleon.
The forward nicked the ball off Terry Kennedy, raced through on goal and confidently slided the ball past Howard to give Latics the lead.
That goal seemed to kick the visitors into action and John Brayford's shot from the edge of the box went over the crossbar without troubling Coleman.
Chris Basham was the next to go close for the visitors as Jamie Murphy's free kick found the defender alone in the area but he couldn't get his foot over the ball and it ballooned away from danger.
Athletic started to come back into the game and Sheffield United's Loius Reed was the first to go into the referee's notebook as he brought down Turner as he knocked the ball past him.
Five minutes before the half time break, Latics' full back Joseph Mills was cautioned for a foul on Ryan Flynn.
Poleon extended Latics' lead on 43 minutes with a goal of the season contender.
The forward received the ball 30 yards out, cut inside two defenders and unleashed a thunderous effort which sailed over Howard's head to put Latics two goals ahead going into the half time break.
Five minutes into the second half and it was the 21-year-old who almost got his hat trick.
Turner held the ball up well in the penalty area, crossed to the back post and Poleon was there but shot wide under a lot of pressure.
Sheffield United did pull a goal back on 56 minutes through Holt.
A cross from the right-hand side was not dealt with inside the penalty box and Holt scrambled the ball over the line to put the Blades back into the game.
Latics needed a response and Philliskirk's volley from the edge of the area almost restored the home side's two goal lead but it went over the crossbar.
With only 20 minutes of the game remaining, Coleman pulled off a wonder save to deny Michael Doyle from distance.
As Latics cleared the first corner into the box, the referee overruled his linesman and awarded another one which proved to be costly for Athletic.
From that corner, United equalised as Murphy forced the ball over the line scoring through a crowd of players.
The referee made himself increasingly unpopular with the home supporters as Latics struggled to get hold of possession.
Two minutes after their goal, the Blades almost took the lead but Doyle's shot from 25 yards cannoned off the inside of the post and away from danger.
Sheffield United pushed for the winning goal but Adam Lockwood cleared the danger inside Latics' box with only five minutes of the game remaining.
As we entered the four minutes of additional time, it was Latics that started to apply the pressure to win the game.
Turner won a free kick right on the edge of the area but Mike Jones could only hit the wall.
Latics kept up the pressure but it came too late as the referee blew the final whistle as the game ended a draw.
Oldham Athletic: Coleman, Mills (Sadler 46'), Wilson, Lockwood, Brown, Kelly, Jones, Winchester, Philliskirk (Murphy 81'), Turner, Poleon.
Subs not used: Kean, B.Wilson, Kusunga, Mellis, Wilkinson.
Sheffield United: Howard, Brayford, Basham, Flynn, Doyle, Murphy, McNulty (Davies 75'), Reed (Scougall 46'), Freeman, Kennedy (Coutts 46'), Holt.
Subs not used: Alcock, Baxter, Done, Turner.
Goals: Oldham Athletic (Poleon 23', 43') 2-2 Sheffield United (Holt 56', Murphy 73')
Attendance: 5,072 (1,862 visiting supporters)