Miller, who is being held in North Korea along with Americans Kenneth Bae and Jeffrey Fowle, was arrested in April after Pyongyang said he ripped up his visa at immigration and demanded asylum.
North Korea said in June it would put Miller and Fowle on trial on unspecified charges related to perpetrating hostile acts.
"The Supreme Court of the Democratic People's Republic of Korea decided to hold on September 14 a court trial on American Matthew Todd Miller, now in custody according to the indictment of a relevant institution," the official news agency KCNA said today.
On September 1, the three men pleaded for their freedom in an interview with CNN.
As government minders looked on, they urged Washington to send an envoy to the isolated authoritarian state to negotiate their release.
"My situation is very urgent," Miller said.
"I think this interview is my final chance to push the American government into helping me," he added, wearing a dark turtleneck and often looking away from the interviewer.
US officials vowed after the footage was aired that they would "leave no stone unturned" in their efforts to free the trio, but declined to disclose details, saying they did not want to jeopardise any diplomacy.
After the North's announcement Sunday, the State Department said there was no update to Psaki's earlier remarks.
Although religious freedom is enshrined in the North's constitution, it does not exist in practice and foreign missionaries -- viewed as seditious elements intent on fomenting unrest -- have been among those detained in the past.
Bae, a Korean-American described by the North as a militant Christian evangelist, was arrested in November 2012 and later sentenced to 15 years of hard labour on charges of seeking to topple the North Korean government.