It looked ominous for Carlos Carvalhal's troops in the first period as the King Power Stadium as the Foxes created plenty of openings. Jamie Vardy finished off an excellent move with a cool finish in the 17th minute.
Fernández equalised shortly after half-time with a thumping header from a corner and that is the way it remained as the Foxes dominated but failed to regain their lead.
Leicester boss Claude Puel made a hatful of changes to the team seen in the 2-1 defeat to Everton on Wednesday evening. Fousseni Diabaté made his Premier League home debut in place of Demarai Gray, whilst Adrien Silva replaced Matty James in the Leicester midfield.
Christian Fuchs was selected at left-back instead of Ben Chilwell and Danny Simpson was named in place of Daniel Amartey. Kelechi Iheanacho started in the league for the first time since October in place of Shinji Okazaki. Wantaway Riyad Mahrez was again not named in the matchday squad.
Meanwhile, Carlos Carvalhal elected for a unchanged line-up from the Swans' 3-1 victory over Arsenal. New signing André Ayew was not ready to be named in the squad. Fellow deadline day recruit Andy King was not eligible against his parent club.
Positive start from Puel's men
In what begun as a nitty-gritty start to the game in which Diabaté picked up a yellow card for a challenge on Sam Clucas, Leicester fired in the opener through Vardy. Harry Maguire powered through the Swans' midfield and found Iheanacho. The Nigerian forward showed good feet and then released his strike partner on goal. The Englishman coolly finished into the far post to notch his 13th goal of the season.
Marc Albrighton then tried his luck from distance but Łukasz Fabiański was equal to his low effort. The Foxes continued to dominate and really should have stretched their advantage. Diabaté raced away through the Swans' defence and tested the goalkeeper. The ball then spun up and fell to Iheanacho who looked to be stroking it home. An excellent clearing header from Alfie Mawson on the line through kept Leicester at bay.
They did eventually have the ball in the net but it was ruled out for offside. Wilfred N'didi chipped the ball home but Diabaté was adjudged to have been offside earlier in the move.
Swansea improve in the second period
The visitors re-emerged from half-time with considerably more vigour than the first-half and it only took them eight minutes to equalise.
Ki Sung-yueng found the head of Fernández from a corner and the Spaniard nodded past a helpless Kasper Schmeichel completely against the run of play.
Whilst Leicester appeared to be taken-aback by the visitors' shock equaliser, they might have regained the lead had Diabaté been slightly more accurate. The Malian forward latched onto a Vardy cut-back but could only place his low shot just inches wide of the post.
Swans earn hard-fought point
The Foxes were finding it considerably more difficult to find their way through the Swansea defence. Demarai Gray, who had replaced Iheanacho, spurned the chance to earn a winner as he volleyed a Fuchs cross high-and-wide.
Whilst Leicester really pushed for a winning goal, they lacked any sort of creativity in the second-half and Swansea earned a highly-credible draw.
Meanwhile, Leicester remain in eighth as they turn their focus to next weekend's clash with Manchester City at the Etihad Stadium.