The spider fauna of Louisiana tabulated here is based only on precise localities for species named in the scientific literature or on specimens in the scientific collections of the Museum of Life Sciences of Louisiana State University in Shreveport. Collections of spiders from northwestern Louisiana during the last 40 years or so have resulted in the recognition of several new records of spiders for the state of Louisiana (34 species), northern Louisiana (14), and northwestern Louisiana (15). Other species (22) are discussed because of major additions to their geographic distributions. Of the 319 species of spiders expected in northwestern Louisiana, 120 (38%) have been collected and verified. Three are under study as possibly representing undescribed species.