Operating profit also jumped 67.9% year on year to Won 9.4 billion for the first three months, compared with Won 5.6 billion in the same period last year. Its Q1 revenue was Won 494.5 billion, down 8.7% from Won 541.8 billion in the year-ago period.
The company attributed the strong earnings to lower raw material costs.
KPIC is South Korea's largest producer of HDPE with a capacity of 530,000 mt/year, accounting for 24% of the country's total production capacity.
The company also has the capacity to produce 470,000 mt/year of ethylene and 470,000 mt/year of polypropylene in the country's main petrochemical complex of Ulsan on the southeast coast.
Net profits at South Korea's largest ethylene producer Yeochun Naphtha Cracking Center however, plunged 67.8% year on year to Won 29.4 billion in the first quarter of the year, compared with Won 97.2 billion a year earlier, the company said in a regulatory filing on May 27.
Its operating profit in Q1 fell 66.2% to Won 44.8 billion, from Won 132.7 billion in Q1, 2012, while Q1 revenue edged down 0.1% year on year to Won 2.02 trillion from Won 2.04 trillion a year earlier.
The company said higher naphtha cost had attributed to the weak earnings. The average import price of naphtha was $961.34/mt for Q1, compared with an average of $943.09/mt a year ago.
YNCC has a total production capacity of 1.91 million mt/year of ethylene from its three steam crackers, accounting for about 25% of South Korea's total capacity. The company is also able to produce 970,000 mt/year of propylene, and 240,000 mt/year of butadiene.