South Korea's trade surplus remained in the black for the 66th month in a row in July amid brisk outbound shipments, customs data showed Tuesday.

The country's trade surplus came to $10.3 billion last month, slightly down from a surplus of $10.7 billion tallied a month earlier, according to the data from the Korea Customs Service.

Asia's fourth-largest economy has posted a monthly trade surplus since February 2012.

It logged $6.7 billion in trade surplus with Southeast Asian countries in July, including a surplus with Vietnam worth $2.4 billion, while it posted an excess of $3 billion in trade with China, its largest trading partner.

Trade with the United States recorded a surplus of $1.6 billion, down from $1.8 billion tallied a year ago, amid the Seoul government's efforts to reduce its surplus with the world's largest economy.

The country's exports have been on a roll since November last year on the back of growing overseas demand for Korean-made semiconductors, petrochemical products and vehicles.

In July, exports jumped 19.5 percent on-year to $48.8 billion, while imports also rose 15.5 percent on-year to $38.6 billion. (Yonhap)