Haza studied in the Conservatoire of Santo Domingo and debuted on 13 March 1958 as a singer, performing at the Instituto de Señoritas Salomé Ureña, arias from Handel's
Messiah, in a chamber concert celebrated in the presence of
Rafael Trujillo. In 1961 she studied at the
Conservatorio Santa Cecilia in Rome with Elena D'Ambrossio, Inés Alfani-Tellini and Roberto Caggiano. She performed there in
Paisiello's
Il duelo. Haza's repertoire covers all the genres of vocal music, including opera, operetta, works with orchestra and songs. With the National Symphonic Orchestra of the Dominican Republic she collaborated with Dominican conductors , Carlos Piantini, Rafael Villanueva, Manuel Marino Miniño, and
José Antonio Molina, and with guest directors such as Roberto Caggiano,
Carlos Chávez,
Enrique García Asencio, Paul Engel and Robert Carter Austin. Among her notable colleagues were Olga Azar, , Luís Rivera, Roberto Caggiano, Lilliam Columna, , Luis Cold Sandoval, Rafael Félix Gimbernard, Rafael Sánchez Cestero, Rafael Félix, , Dagmar White, Creole Hidalgo, Fausto Cepeda, Luis Cold, Rafael Gil Castro, Vito Castorina, and Enriquillo Cerón. Haza sang works by
Maurice Ravel,
Heitor Villa-Lobos,
Lukas Foss, José of Jesús Ravelo,
Leo Brouwer and Enrique of Marchena, among others. She played leading roles in operas such as Mascagni's
Cavalleria rusticana, Leoncavallo's
Los Payasos, and
zarzuelas including Torroba's
Luisa Fernanda, '
, and '. Outside of the Dominican Republic, she performed in the United States, Puerto Rico, Mexico, and Cuba. She participated with pianist
Manuel Rueda in the Latin Festival-American of the Arts. In 1988, she participated in the Festival Cervantino in Mexico and the Dominican Republic with the pianist María of Fátima Geraldes. That same year she recorded the CDs
Entrega (Delivery),
Joyas de Navidad (Joy of Christmas) and
Sueños (Dreams). On the occasion of her 50th anniversary as a singer, a concert was staged at the National Theatre, conducted by . Additionally, Haza taught during many years in the National Conservatoire of Music, and was artistic director of the
National Theatre for five years. She also directed the Lyric Singers of Fine Arts. She also worked as a speech therapist. A book about Haza and her career,
Ivonne Haza: la diva dominicana (The Dominican
diva), was published in 2011, presented in a ceremony by the
Central Bank of the Dominican Republic which published it. Haza was awarded the Order of the Dominicos of Duarte of Sánchez and Mella of the Dominican Republic and the
Order of Merit of Italy. She received an honorary doctorate from the
Universidad Autónoma de Santo Domingo. == Personal life ==