Born in Palermo, son of painter Pietro Martorana, Gioacchino learned the craft of painting from his father. Martorana developed his craft in Rome where he joined the workshop of Marco Benefial. Under the guidance of Benefial, Martorana painted the series of eight stories of S, Benedetto -of which only “Benedetto e Totila”, “Benedetto e l’ossesso”, “Benedetto distribuisce il Tesoro”, and the “Comunione di s. Benedetto are left. After spending a few years in Rome, his only known production in Rome being the “Madonna e i ss. Gaetano da Thiene e Giuseppe Calasanzio” in S. Dorotea, Martorana moved back to Sicily. In Palermo, he produced works for the archdiocesan seminary of Monreale (“Immacolata Concezione” “Trionfo della Religione”), Palazzo Natoli (“Giustizia”, “Carita'”, “Trionfo dell’amore”, and “Assunzione di Maria”), St. Francis Xavier (“Il Cuore di Gesù” and “Il Cuore di Maria”), and his masterpiece, the great altarpiece of the Trinity and virgin (Palermo).
Martorana was also a great portraitist. During his career, he painted portraits for the Prince of Gravina (Palermo, Comitini palace) and the viceroy G. Fogliani (Palermo, the Norman Palace, Castelnuovo Fogliani and Caschi Lavagetto). In 1770 he realized paintings for the palace of the Prince Gravina di Comitini (The triumph of true love), the Constantine Palace (‘Allegory of Abundance with Diana and Endymion’), the Paterno’ palace (‘The Glory of the family Asmundo and Apollo crowned by Minerva’), the Guggino-Bordonaro building (‘Allegory of Love’), the palace of the Marquis of Santa Margherita.
In his later years, Martorana worked together with Ermenegildo and his other children painting for the Oratory of St. Filippo Neri (“Vergine, 1777), the church of the Royal Hotel of the poor, and the Branciforte Palace. Martorana died in Palermo on November 27, 1779.