Around 2.5 million women and girls in northeast Spain will be able to buy a menstrual cup, underwear for menstruation and two packs of pads free of charge from pharmacies.
The free products will come from the recycling of used pads.
The Catalan government announced that the initiative, called "My period, my rules", aims to "guarantee the right to menstrual equality".
In a regional government survey, 23 percent of women said they reuse disposable hygiene products for economic reasons.
Tània Verge, Catalonia's minister for equality and feminism, said: "For decades, women's sexual and reproductive rights have been at the center of feminist struggles on a global scale. This makes our country a fairer place," said Tània Verge.
The distribution of reusable products also aims to reduce waste.
The regional government says Catalonia produces around 9,000 tons of waste from disposable feminine hygiene products.
The reusable products are purchased by the public health system, which covers the entire population, and distributed by Catalonia's more than 3,000 private pharmacies.
The cost of the program to the regional government was estimated at 8.5 million euros.
Last year, Spain's national government passed a law granting paid medical leave to women suffering from severe menstrual pain.
