The Beijing Ming City Wall Ruins Park (traditional Chinese: 北京明城牆遺址公園; simplified Chinese: 北京明城墙遗址公园; pinyin: Běijīng Míng Chéngqiáng Yízhǐ Gōngyuán) is a park in Beijing with the longest and best preserved section of the city's Ming Dynasty city wall. The park is located 3 km (1.9 mi) from the city center and extends east from Chongwenmen to Dongbianmen and then north to near to Beijing Railway Station East Street. The park features a 1.5 km (0.93 mi) section of the Ming city wall and the Southeast Corner Tower, which are over 550 years old and surrounded by green park space to the south and east. The park covers an area of 15.5 ha (38 acres), including 3.3 ha (8.2 acres) of fortifications and 12.2 ha (30 acres) of green space. The corner tower and the ramparts atop the wall can be accessed for an admission fee.

The park is located at the southeast corner of Beijing's inner walled city, about 3 km (1.9 mi) southeast of Tiananmen Square in what is now Dongcheng District, just inside the Second Ring Road. Preserved in the park is a section of the Ming city wall and the Southeast Corner Tower, that once connected Chongwenmen and Dongbianmen, two city gates that have been replaced with roadway intersections. The longer southern city wall is attached to the Southeast Corner Tower itself while a shorter section of the eastern city wall is separated from the corner tower by a railway out of the Beijing railway station. Park space at the foot of the southern city wall extends along Chongwenmen East Avenue to the Second Ring Road. The Beijing Ancient Observatory, built atop another section of the eastern city wall at Jianguomen, is a short walk north of the corner tower. The Beijing railway station and its rail depots occupy the area immediately north of the park.

The corner tower's exhibits and ramparts are open from 8:00 am to 5:00 pm. Admission is Y10 for adults, half-price for students. Children below 1.2 m in height and senior citizens are admitted for free. The park space is not enclosed and is accessible to the public at all hours. The park is popular with tourists visiting the wall and residents from the surrounding neighborhood, who use the green space for recreation and dog walking. The park hosts the annual Huashi Saturn Peach Temple Festival.

The Ming City Wall Relics Park is accessible by Beijing Bus to "Dongbianmen" bus stop (Routes 25, 29, 39, 43, 44, 59, 434, 525, 610, 674 and 特2), "Chongwenmen East" bus stop (Routes 12, 25, 39, 43, 44, 525, 610) and "Jianguomen South" bus stop (Routes 25, 39, 43, 44, 52, 122, 434, 637, 638, 750 and 特2); and by Beijing Subway to Chongwenmen (Line 2) and Jianguomen station (Lines 1 and 2).

Beijing's inner city wall was built during the Ming Dynasty in 1419. The Ming city walls stood for nearly 550 years until the early 1960s when most of the gates and walls were torn down to build the Beijing Subway, which runs underneath where the walls stood. The subway's inner loop line turned into the Inner City at Chongwenmen to stop at the Beijing railway station, and did not need to run beneath a section of the wall at the southeast corner of the Inner City. Of the 40 km of the original wall, only this 1.5 km section was spared. Inside this section of the wall (north of the wall) are railway yards of Beijing Station. Outside the wall (south of the wall) stood residential homes and small businesses.

In the late 1990s, the city government decided convert the remnants of the wall into a park and relocate the small businesses and homes between the foot of the southern city wall and Chongwenmen East Avenue. The relocated businesses and residents received compensation and tax exemptions. Construction began in November 2001. The homes, which lacked indoor heating, plumbing and running water, were razed but large trees that stood in the courtyards were preserved. To preserve the historical integrity of the fortifications, the authorities solicited donations of Ming era bricks from city residents to use in the restoration. About of one-fifth of 2,000,000 bricks used in the restoration are from the Ming-era. When the park was completed in September 2003, national leaders Jiang Zemin, Li Lanqing, Wan Li, Ding Guangen, and then municipal party secretary Jia Qinglin and mayor Liu Qi, visited the park.

The Southeast Corner Tower was built from 1436 to 1439 and is a major state-protected historical site. The tower, which rises 29 m (95 ft) in height with 144 archery windows, is the largest corner tower still standing in China. The tower could house 200 soldiers and has ramps for soldiers and horses. During the Qing Dynasty, bannerman of the Plain Blue Banner were stationed at the corner tower. During the Boxer Rebellion of 1900, the tower was attacked and captured by the Eight-Nation Alliance. It was known by Westerners as the Fox Tower. Graffiti carved by the invaders are preserved inside the tower. The corner tower was restored in 1983 and became a tourist site. Inside the tower is an exhibit on the history of the city's Ming-era walls. The Red Gate Gallery, a privately managed, non-profit contemporary art gallery opened in 1991 inside the tower and operated for over two decades before moving to the 798 Art Zone. In 2003, the Southeast Corner Tower became part of the Ming City Wall Relics Park.