SEOUL, KOREA — The court imposed a limited ban on national sales of products by both companies covered by the ruling.
It ruled that US-based Apple had infringed two patents held by Samsung, while the Korean firm had violated one of Apple's patents.
The decision comes as a jury in California is deliberating on a patent trial between the two firms in the US.
The sales ban will apply to Apple's iPhone3GS, iPhone4 and its tablets the iPad and ipad2.
Samsung products affected by the ban include its smartphone models Galaxy I and II and its Galaxy Tab and the Galaxy Tab 10.1 tablet PCs.
The court ordered Apple to pay 40m won ($35,000; £22,000) in damages to the South Korean rival, while Samsung was told to pay Apple 25m won.
Source: BBC News