Nagano Olympic Stadium, Olympic stadium and baseball venue in Nagano, Japan

The Nagano Olympic Stadium is a sports facility in Nagano with fixed seating for around 30,000 spectators within the Minami Nagano Sports Park. The building now operates primarily as a baseball venue used by local teams.

The stadium's infield stand was built first, in time for the 1998 Winter Olympics opening and closing ceremonies, while a temporary steel stand occupied the outfield. Construction resumed in spring 1998, and the ballpark opened on 16 April 2000 with 99.1 m foul lines and a 122 m centre field. It replaced the ageing Nagano Castle Mountain ballpark, which closed in November 2000.

The stands are shaped after cherry blossoms: the two-tiered infield stand forms the petals, and the six floodlight towers stand for the flower's centre. The nickname was chosen by public competition; many entries referred to the Olympics, so the city adopted "Olympic", approved by the IOC on 1 February 2000. The Olympic rings appear only on the front balcony and the entrance emblem.

The stadium is in Minami Nagano Sports Park in Shinonoi Higashifukuji, Nagano. From JR Shinonoi Station's east exit, the Shinonoi Gururin community bus reaches Minami Nagano Sports Park, but only four of eleven weekday runs pass the park and none run on weekends or holidays; the station is about 8 minutes by taxi or 30 minutes on foot. Shuttle buses run from Nagano Station's east exit and Shinonoi Station's west exit on pro baseball game days, and the Nagano Interchange of the Joshinetsu Expressway is about 5 minutes away by car.

The nickname was chosen by public competition, and the city settled on "Olympic" after many entries referenced the 1998 Games. The IOC approved it on 1 February 2000 on condition that the Olympic rings not be used freely; they appear only on the front balcony and at the main entrance.