Excessive release of proinflammatory cytokines by activated microglia surrounding senile plaques might contribute to the neurodegeneration associated with Alzheimer’s disease (AD). Poly(ADP-ribose) polymerase 1 (PARP-1) is a nuclear protein recently implicated in the initial inflammatory response by modulating expression of inflammation-related genes, like interleukin 1 (IL-1). As PARP-1 overactivity has been shown in the AD brain, we tested the hypothesis that the PARP-1 –410 and –1672 polymorphisms would predispose people to AD due to overexpression of the PARP-1 gene, independently or in concert with the proinflammatory IL-1A –889 polymorphism. So, we performed a case-control study in 263 Spanish AD patients and 293 healthy controls. PARP-1 –410 and PARP-1 –1672 haplotypes were associated with an increased risk for AD (global haplotype association p value = 0.019), and, in addition, PARP-1 haplotypes increased the risk of AD by interaction with the IL-1A –889 allele 2.