Paldus was born in Bzí, Czech Republic. In 1961 he received a PhD in physical chemistry at the Czechoslovak Academy of Sciences. In 1995 he became DrSc at the Charles University in Prague and in 2006 he became Dr.h.c. at the Comenius University in Bratislava. Following the invasion of former Czechoslovakia by Warsaw pact armies in August 1968, he left his native country and became associate professor at the University of Waterloo in Canada. In 1975 he was promoted to full professor. He retired from the University of Waterloo in 2001. In 1983 Paldus was elected Fellow of the Royal Society of Canada. Since 1984 he is a member of the International Academy of Quantum Molecular Science. Josef Paldus (co)authored more than 290 scientific papers.
^Paldus, J.; Čížek, J.; Shavitt, I. (1972). "Correlation problems in atomic and molecular systems. IV. Extended coupled-pair many-electron theory and its applications to the BH3 molecule". Phys. Rev. A5: 50–67. Bibcode:1972PhRvA...5...50P. doi:10.1103/PhysRevA.5.50.