Catholic Church-run shelters in the New Orleans, Miami and Seattle areas of the US are each receiving $5 million from a charity created by Mr Bezos and her wife, MacKenzie.
He said: "We hope these grants provide the additional resources these leaders and their organisations need to expand the scope and impact of their efforts."
The charities are among 24 organisations each taking a share of $97.5 million in grants. All the groups selected either help tackle homelessness or provide pre-school care in deprived areas.
Catholic Charities of the Archdiocese of Miami said it was "grateful" to the Bezos family for the funding it received through the Day 1 Families Fund.
Chief executive, Peter Routis-Arroyo said: "We are grateful to Jeff and MacKenzie Bezos for their generous and timely Day 1 Families Fund grant that allows Catholic Charities of the Archdiocese of Miami to be at the forefront of providing social services to children and families experiencing homelessness in the tri-county area of South Florida."
Denny Hunthausen from Catholic Community Services of Western Washington told Northwest Catholic the grant it received "will have a considerable impact on family homelessness in Pierce County".
Meanwhile, Catholic Charities of the Archdiocese of New Orleans said extra money will help it "meet the needs of so many families experiencing homelessness in our community".
The net worth of 54-year-old Jeff Bezos, who founded Amazon in 1994, was valued by Forbes earlier this year as $140.2 billion.
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