The proposal is the first formal overture by the government of President Moon Jae-in, who came to power in May pledging to engage the North in dialog, as well as to apply pressure on Pyongyang to reduce tension on the Korean peninsula.
"We request military talks with the North on July 21 at Tongilgak to stop all hostile activities that raise military tension at the military demarcation line," South Korea's Vice Defence Minister Suh Choo-suk told a media briefing.
Tongilgak is a North Korean building at the Panmunjom truce village on the border used for previous inter-Korea talks. The last government-level talks were held in December 2015.
The proposal came roughly a week after Moon said the need for dialog with North Korea was more pressing than ever to curb Pyongyang's nuclear and missile programs.
The vice defense minister did not elaborate on the meaning of hostile military activities, which varies between the two Koreas. South Korea usually refers to loudspeaker broadcasts and other provocations, while the North wants a halt to routine joint US-South Korea military drills.
Moon has suggested hostile military activities be halted at the inter-Korean border on July 27, the anniversary of the 1953 armistice agreement that ended the Korean War.
The South Korean Red Cross on Monday proposed talks with the North to discuss reunions of family members separated during the Korean War. It suggested talks be held on August 1, with possible reunions over the Chuseok holiday, which falls in October this year.
Pyongyang has repeatedly said it refuses to engage in all talks with the South unless Seoul turns over 12 waitresses who defected to the South last year.
North Korea says the South abducted the 12 waitresses and the restaurant manager and has demanded their return, but the South has said the group decided to defect of its own free will.
The North has conducted two nuclear tests since the beginning of last year and missile-related activities at an unprecedented pace.
It conducted the first test of an intercontinental ballistic missile (ICBM) earlier this month, claiming to have mastered the technology to mount a nuclear warhead on the missile. South Korea and the United States dispute the claim.In an act to rein in the North, the United States is preparing new sanctions on Chinese banks and firms doing business with Pyongyang possibly within weeks, two senior US officials said last week