In July 2017, chlorotic and necrotic mottle, red lesions, and wrinkling of the leaf blade were observed on leaves of rhubarb (Rheum rhabarbarum) plants in commercial plantings in southeast Poland. Samples were taken from 10 symptomatic and four asymptomatic plants and were tested by enzyme-linked immunosorbent assay with commercially available antibodies against Arabis mosaic virus (ArMV), Turnip mosaic virus (TuMV), Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV), Tobacco ringspot virus (TRSV), Tomato spotted wilt virus (TSWV) and Tomato black ring virus (TBRV). The presence of ArMV was confirmed in two plants exhibiting foliar chlorotic mottle, one of which was coinfected with TBRV. All 14 samples tested negative for TuMV, CMV, TMV, TRSV, and TSWV. To confirm the presence of ArMV, total nucleic acids were extracted from rhubarb leaves and subjected to reverse-transcription polymerase chain reaction (RT-PCR). Sequencing results of the PCR products confirmed that two plants were infected with ArMV. The sequences of two ArMV isolates from rhubarb (GenBank accession nos. MG882691 and MG882692) shared 88.6 and 93.1% nucleotide and amino acid identity, respectively, and high identities with other ArMV isolates, including GenBank accession numbers EU617327 from Ligustrum vulgare and KJ481199 from narcissus with up to 92% nucleotide identity. This is thought to be the first report of ArMV in rhubarb in Poland.