More than 50% of workers earned less than 1,000 euros per month last year while rents and house prices have skyrocketed.
Prime Minister Antonio Costa told a news conference the crisis was now affecting all families, not just the most vulnerable.
It is not clear when the measures, worth at least 900 million euros ($962.19 million), will come into effect.
To address the housing shortage, Costa said the state would rent vacant houses direct from landlords for a period of five years and put them on the rental market.
At a small housing protest in Lisbon, 23-year-old activist Andreia Galvao accused the government of failing to live up to promises it made to address the housing crisis in the past.