Abstract Brazil is characterized as a megadiverse country, and one of the factors that guarantees the knowledge and preservation of this biodiversity is an improvement in the biological collections. They represent a country's biological, scientific, cultural, and genetic heritage and their preservation depends on a joint effort of researchers, institutions, and public authorities. Marine biological collections of invertebrates and algae of the state of São Paulo represent a high percentage of the national collections, with five biological collections deposited in state institutions. Currently, these collections safeguard the vast majority of the state's marine collection and make up one of the largest in the country. Therefore, the objective of this research is to present information on marine biological collections in the state of São Paulo, their current status, funding, and future perspectives, creating communication opportunities and considering the factors that impact their development. Support from the São Paulo Research Foundation (FAPESP) surpasses state limits, since many studies address broader areas and/or establish diverse partnerships with other institutions from outside São Paulo. This is reflected in the taxonomic and geographic scope of the biological collections in the state, since these host specimens/species from different regions of the country, or even from other countries. However, it is worth mentioning that it is not enough to invest in expeditions to enrich the collections without valuing the training of qualified personnel, both for the collections maintenance and for their taxonomic refinement.