Prosecutors said Dykstra sold sports memorabilia and household items, including a $50,000 sink, from his California mansion before creditors could liquidate them, the Los Angeles Times reported Tuesday.
An affidavit filed by the FBI said Dykstra transferred dozens of items to a consignment store that paid him cash for a truckload of goods. Many of the items later appeared for resale on Craigslist and eBay.
In addition to the prison sentence, U.S. District Judge Dean Pregerson ordered Dykstra to pay $200,000 in restitution and to perform 500 hours of community service.
He is already serving a three-year prison sentence for auto theft and earlier this year received a nine-month jail sentence for exposing himself to a woman.
Nicknamed "Nails" by baseball fans, Dykstra helped the Mets win the 1986 World Series.