South Korea's largest companies saw their second-quarter profits soar, with operating income more than doubling compared to the same period last year, primarily due to strong gains in the semiconductor sector.

A report by CEO Score revealed that 334 of the top 500 companies by sales in South Korea achieved combined net profits of 59.4 trillion won ($43.6 billion) between April and June, representing a 107.1% increase from 28.7 trillion won the previous year.

Total sales for these companies also rose 7% year-over-year, reaching 779.5 trillion won, up from 728.6 trillion won, according to data from Yonhap News Agency. The report includes companies that had released their quarterly financial statements by Wednesday.

Leading this profit surge were South Korea's two semiconductor giants, Samsung Electronics and SK hynix, which benefited from the growing demand for AI semiconductors, such as high-bandwidth memory (HBM), from U.S. tech companies like Nvidia Corp.

Samsung Electronics, the world's largest memory chipmaker, posted an operating profit of 10.4 trillion won for the quarter ending in June, a significant leap from 668.5 billion won a year earlier, solidifying its status as the country's most profitable company.

SK hynix followed closely, with an operating profit of 5.5 trillion won for the second quarter, a sharp turnaround from an operating loss of 2.9 trillion won in the same period last year. This pushed SK hynix to the second spot in operating profits, surpassing automotive leaders Hyundai Motor Co. and Kia Corp., which reported operating profits of 4.3 trillion won and 3.6 trillion won, respectively.

However, not all sectors performed as well. SK On, the battery manufacturing subsidiary of SK Group, reported the largest operating loss of 460.2 billion won during the quarter, amid declining global demand for electric vehicles. The chemical industry also faced challenges, with Lotte Chemical Co. and Hanwha Solutions Corp. posting operating losses of 111.2 billion won and 107.8 billion won, respectively.