The firms on either the top-tier Kospi and second-tier Kosdaq recorded a total of 121.7 trillion won ($112.4 billion) in net profit and 155.6 trillion won in operating profit, up 48.5 percent and up 45.8 percent on-year, according to data compiled by local market tracker CEOScore.
Their combined net revenue also surged 11.7 percent and came to 1,525.2 trillion won in 2017, data also showed.
CEOScore collected data for the 81 of the top 100 firms, as of Friday, that have 2017 earnings data available.
Of the 81 firms, only two firms -- shipbuilder Samsung Heavy Industries and joint disease treatment developer TissueGene -- reported operating losses, worth 524.2 billion won and 15.4 billion won, respectively.
By sector, the biotechnology sector took the biggest leap forward, seeing a 154.3 percent surge in total operating profits, followed by the brokerage sector and information technology sector, which saw 124.1 percent and 112.4 percent increases. Automakers and public utilities, in contrast, suffered declines in operating profit of 29.4 percent and 14.2 percent.
By Son Ji-hyoung