In 2011, a study by our group demonstrated that Aβ induces neurodegeneration also by significantly suppressing the expression of VDR. We also reported that the expression of mRNA for 25-hydroxyvitaminD3–24-hydroxylase (24OHase) encoded by CYP24, the enzyme that accelerates vitamin D catabolism, is induced by Aβ in hippocampal neurons. This finding suggests that the involvement of vitamin D with AD includes also the disruption of vitamin D metabolism and action. The present study investigated the expression levels of miRNAs that were suggested to regulate VDR (hsa-mir-27b-3p, hsa-let-7a-5p, hsa-mir-125b-5p), CYP24 (hsa-mir-125b-5p) in order to evaluate whether alteration of the expressions of VDR or 24(OH)ase by amyloid beta involve these miRNAs or not? 24, 48 and 72 hours of Aβ, vitamin D, vitamin D+Aβ and Aβ+vitamin D treated groups and untreated control groups were established in the primary cortical neuron cultures of Sprague Dawley rat embryos. Amyloid pathology was established with the treatment of 10 μM of Aβ1–42. Vitamin D groups were treated with 10-8M 1α-25dihydroxyvitamin D3 (1,25(OH)2D3). The expressions of let-7a, miR-27b-3p, miR-125b-5p, miR-26b-5p, miR-192–5p, were investigated with qRT-PCR. Our results indicated that only let7a-5p expression was significantly increased in amyloid beta treated cortical neurons at 24 hours of treatments. miR125b-5p expression decreased in both amyloid beta or vitamin D treated ones, yet the attenuations were not statistically significant. miR125b-5p expression also decreased in amyloid beta, amyloid beta+vitamin D, vitamin D+amyloid beta treated groups in 48 hours of treatments compared to control groups. miR27b-3p expression induced in vitamin D treated neurons at the 24 and 48 hours of treatments compared with the control groups. Consequently, our preliminary results indicate that miR27b-3p might be involved in regulation of vitamin D action, by regulating VDR expression. The more likely small RNA that is involved in VDR suppression by amyloid beta might be let7a-5p. CYP24 induction by amyloid beta might involve the suppression of miR125b-5p by amyloid beta. (The present work was supported by the Research Fund of Istanbul University, Project no:21585 and by the Scientific and Technological Research Council of Turkey-TUBITAK, Project no:214S585.)