Born in Buenos Aires in 1921, Juan Alberto Molenberg studied at the Schools of Fine Arts Manuel Belgrano and Prilidiano Pueyrredon, graduating as a Drawing Professor.
He was a charter member of the Asociación Arte Concreto-Invención. He participated in the exhibitions the group had in 1946 - at the Salón Peuser in March; at the Centre of Graduated Professors of Secondary Teaching in September; at the Sociedad Argentina de Artistas Plásticos (SAAP) in October; and at the Ateneo Popular de La Boca in the same month.
In the early 50s he collaborated in Contemporánea magazine.
He worked as a sketcher and designer of advertisements, labels and logotypes, specialized in packaging, and collaborated in Art Departments of commercial companies.
In Buenos Aires, he took part in the Homenaje a la vanguardia argentina de la década del ’40 (ATribute to the Argentine Avant-garde of the 40s) exhibition, hosted by Galería Arte Nuevo (1976); Vanguardias de la década del ’40. Arte Concreto-Invención. Arte Madí. Perceptismo (Vanguards of the Decade of the '40, Arte Concreto-Invención 1945, Madí Art, Perceptismo), at the Museo Eduardo Sivori (1980).
He lives in Buenos Aires.