Strong interest in 3D TVs during the first three months of this year saw LG's TV division returning to profitability, offsetting the company's still loss-making mobile phone business.
The company also showed an operating profit for the first time in nine months.
However, Samsung is blaming its lowest operating profit for almost two years on a slump in sales of its LCD TVs, while mobile phones were more successful for the company.
LG had sales of KRW13.16tn (£7.45bn) in the first three months of this year, and showed an operating profit of KRW130.8bn (£74m).
Particularly impressive was the performance of the company's TV division, buoyed by 3D TV sales: it turned a loss of KRW65.2bn (£37m) in the last quarter of 2010 into a KRW82.1bn (£46.5m) profit in the first quarter of this year.
Meanwhile the company's mobile phone division, while still making a loss, is showing some signs of improvement: losses in January-March this year were KRW100bn (£56m), compared to KRW260.5bn (£147m) in the previous quarter.
Samsung, however, has seen its profits fall to the lowest level since the second quarter of 2009: it made KRW2.95tn (£1.67bn) in the first three months of this year, compared to KRW4.41tn (£2.5bn) in the same quarter last year.
Sales were up 6.8% year-on-year at KRW36.99tn (almost £21bn), but down 11.6% on the last quarter of 2010.
A major cause of this reduction is a slump in the sales of LCD panels and TVs: Samsung's LCD business saw a loss of KRW230bn (£130m) for the quarter, and the company recently announced that it and Sony are reducing the capital holding in their S-LCD panel-making joint venture.
However, Samsung's mobile phone business was rather healthier, sales of the Galaxy S smartphone helping it to a profit of KTRW1.43tn. (£809m).