Saldanha (64), who also holds the portfolios of Science and Environment, was brought to a private hospital at around 1.30 am after he suffered massive cardiac arrest.
The doctors treating him told PTI that they tried to resurrect him for almost two hours before declaring him dead.
The body has been shifted to Goa Medical College and hospital near here. Chief Minister Manohar Parrikar also rushed to the hospital.
The BJP legislator representing Cortalim constituency was sworn-in as the minister on March 9 after BJP won the Goa Assembly elections.