1950 Instituto Chileno-Norteamericano de Cultura, Valparaiso, Cile
1956 Instituto de Arte Contemporaneo, Lima, Peru Galería El Sotano, Concepcion, Chile Instituto Chileno-Britanico, Santiago, Cile Instituto Chileno-Frances, Santiago, Chile
1961 Galería Nebli, Madrid, Spain Primera exposición del Grupo Hondo, Galería Nebli, Madrid, Spain
1962 Museo de Arte Contemporaneo, Barcelona, Spain Salón de Mayo, Barcelona, Spain
1963 Ateneo de Madrid, Spain Segunda exposición del Grupo Hondo, Museo Español de Arte Contemporaneo, Madrid, Spain Arte Actual de America y España, Palacio Velazquez, Madrid, Spain
1964 Gallerie Entracte, Lausanne, Switzerland Galeria Diario de Noticias, Lisboa, Portugal Spanish Pavillion, Word Fair, New York, USA Exposicion Inaugural Galeria Juana Mordó, Madrid, Spain
1965 Springer Gallery, Berlin, Germany Nueve pintores españoles, Palacio de la Virreina, Barcelona, Spain
1966 The Contemporary Art Museum and Institution, PanAmerican Union, Washington D.C., USA Galeria Carmen Wough, Santiago, Chile
1967 Bienville Gallery, New Orleans, USA Pintores Españoles Contemporaneos, Club de Sevilla de la Facultad de Derecho, Sevilla, Spain Martha Jackson Gallery, New York, USA
1968 Simone Stern Gallery, New Orleans, USA Dirección General de Bellas Artes, Madrid, Spain
1970 Galleria Christian Stein, Torino, Italy Padiglione Spagnolo, XXXV Biennale di Venezia, Venezia, Italy
1971 Galleria Schubert, Milano, Italia Bienville Gallery, New Orleans, USA
1973 Annely Juda Fine Art, London, United Kingdom Galleria dell’Orso, Milan, Italy
1974 Galeria Juana Mordo, Madrid, Spain Galleria S. Michele, Brescia, Italy Salas de la Cultura de la Caja de Ahorros de Navarra, Pamplona, Spain Galleria Borgo, Treviso, Italy Galleria Fidesarte, Venezia, Italy Opening Exhibition: The Collection & Museum: The Hirshhorn Museum & Sculpture Garden, Washington D.C., USA
1975 Arte Fiera, Bologna, Italy
1976 Galleria Santa Croce, Firenze, Italy Galleria Juana Mordó, Madrid, Spain Internationale Kustmesse, Basel, Switzerland Arte Fiera, Bologna, Italy
1977 Chile, l’espoir, Maison de la Culture Andre Malraux, Reims, France
1978 Orellana One Man Show, FIAC, Paris, France
1979 Galleria Forni, Bologna, Italia
1980 Bienville Gallery, New Orleans, USA Triennale Internazionale d’Arte, Palazzo Reale, Monza, Italy Omaggio al Cile di Orellana, Fortezza del Priamar, Savona, Italy
1981 Contemporary Art in Spain & America, from the Permanent Collection of the Hirshhorn Museum and Sculpture Garden, Hirshhorn Museum & Sculpture Garden, Washington D.C., USA
1983 Ceramiche Sculturali, Museo della Ceramica, Albisola, Italy Oratorio S. Agostino, Alta Val Bormida, Italy
1984 Museo de Arte Moderno Casa Lis, Salamanca, Spain
1985 Orellana alla Villa Barilli, Carcare, Italia Homenaje a Juana Mordo, Circulo de Bellas Artes, Madrid, Spain
1986 Orellana 1970 – 1986, Museo Espanol de Arte Contemporaneo, Madrid, Spain ARCO, Madrid, Spain Spagna Come Realtà – Aspetti della Pittura Spagnola Contemporanea, Ascoli Piceno, San Benedetto del Tronto, Italy
1990 Albisola, gli artisti e la ceramica, Albisola, Italy Albisola Ceramica 90 a Milano, Refettorio delle Stelline, Milano, Italy Mostra antologica allo Spazio Ansaldo, Milano, Italy
1992 Retratos de Artistas, Juan Dolcet, MNCARS, Madrid, Spain
1993 Taipei Fine Arts Museum, Taipei, Taiwan
1994 Centro Cultural Provincial, Palencia, Spain
1995 O Novo Orellana, Museo Casa Das Artes, Vigo, Spain
1998 ARCO, Galleria Christian Stein, One Man Show, Madrid, Spain
1999 ArteFiera, Galleria Christian Stein, Bologna, Italy Bronx Around, Complejo Cultural San Francisco, Diputación Provincial, Cáceres, Spain
2002 Mediterrània, Museo Civico d’Arte Moderna, Palazzo d’Avalos, Abruzzo, Italy
2004 Arte Per Immagini: Da De Chirico A Lopez Garcia, Museo d’Arte Costantino Barbella, Palazzo Martinetti-Bianchi, Chieti, Italy
2005 La Bellezza della Croce, Museo Vaticano Santa Casa di Loreto, Loreto, Italy Il Male, Palazzo di Caccia Stupinigi, Torino, Italy
2006 Orellana au Château d’Harcourt, Chauvigny, France
2007 Naturaleza del Presente, Museo Malpartida, Caceres, Spain El Sueño, Sala Comunale Palace, Spotorno, Italy Las Cronicas – Les Chroniques, École D’Arts Plastiques, Châtellerault, France Gastón orellana a Villa Cambiaso, Savona, Italy
2008 The New York Graphic Workshop: 1965- 1970, Blanton Museum of Art, Austin, Texas, USA Centenario Salvador Allende, Obras del Museo de la Solidaridad, Centro Cultural Palacio de la Moneda, Santiago, Chile
2012 Nel Segno Dell’immagine: Da Sassu a Ortega, Museo Palazzo di Mayo, Chieti, Italy
2014 Il Fascino Dell’immagine, Tradizione E Modernità, Museo Vittoria Colonna, Pescara, Italy
2017 Gastón Orellana – Dell’attimo Perenne, Catania, Italy