Home-grown movies had a combined share of 50.1 percent in the box office in 2014, the ministry said based on data complied by an integrated ticket sales computer network run by theaters nationwide.
The figure marks a decrease of 9.6 percentage points from 59.7 percent tallied in 2013.
Market watchers attributed the decline to the success of Disney animation film "Frozen" and Hollywood sci-fi epic "Interstellar."
South Korean and imported movies attracted an all-time high of 215 million moviegoers in 2014, up 0.8 percent from the previous year, the ministry said.