Estadio Ricardo Saprissa Aymá, football stadium in San Juan de Tibás, Costa Rica

Estadio Ricardo Saprissa Aymá is a football stadium in San Juan de Tibás, cantón of Tibás, San José province, with a real capacity of 21,397 spectators, making it Costa Rica's second-largest football venue. The pitch is natural grass, and the stands rise in tiers: a lower band of red, yellow and white seats spells "SAPRISSA", with two upper tiers of dark red seats under a flat steel-truss roof.

Ricardo Saprissa first sought a permanent site in 1955, and the club bought a coffee plantation in San Juan de Tibás on 3 August 1965 for ₡363,398.90. Saprissa laid the first stone on 12 October 1966, and the stadium opened on 27 August 1972 with a 1-1 draw against Comunicaciones of Guatemala; Peter Sandoval scored the visitors' goal and Eduardo Chavarría equalised from a penalty.

The stadium is nicknamed "La Cueva del Monstruo" (The Monster's Cave) after Deportivo Saprissa's nickname "El Monstruo Morado", the Purple Monster. The southern stand, the largest with 4,186 seats, holds the club's hardcore supporters' group, called Ultra Morada. The stands sit so close to the pitch that visiting players have complained about it, and United States players have called it one of the hardest places to play.

The stadium sits in San Juan de Tibás, north of central San José, and is reached by bus or car. The stands rise close to the pitch, so the upper tiers of the east and west sides give the widest view of the field. Arrive early on match days, when the surrounding streets fill with fans.

In 2003, FIFA granted Saprissa permission to replace the natural grass with synthetic turf, making it the only stadium in Latin America with that surface at the time. In 2005 it became the first venue to host a World Cup qualifier on FieldTurf; the club returned to a natural pitch in 2015. Alexi Lalas called it more daunting than the Azteca.