SK Telecom has reported a 10.4% decline in net profit for 2011, after a sharp 61% slump for the fourth quarter.
The company posted a net profit for the year of 1.58 trillion won ($1.41 billion), from 2.2% higher revenue of 15.95 trillion won.
SK Telecom blamed recent cuts to its mobile rates - implemented under pressure from regulator KCC - for its profit decline, as well as increased investment in network upgrades.
But the operator added that growth in wireless internet earnings contributed to the increasing revenue.
The profit impacts were worst in the fourth quarter, during which SK Teleom's net profit fell 61% year-on-year to 196 billion won.
Operating profit likewise fell 35.7% to 329.4 billion won, and revenue fell 2.3% to 3.93 trillion won, AFPsaid.