Buffalobur (
Solanum rostratum
Dunal), which belongs to the Solanaceae family, is a worldwide noxious invasive weed and is listed as one of the top 10 alien invasive species in China. It is harmful to humans and livestock because the entire plant is covered with spines containing toxins. Many studies have analysed the gene expression in this weed species under different stress conditions using quantitative real-time PCR (qPCR). However, until now, there has been no report on suitable reference genes in buffalobur. Herein, 14 candidate reference genes were selected and evaluated for their expression stability in buffalobur in different tissues, at different developmental stages, and in response to several stress conditions using the geNorm, NormFinder, BestKeeper and RefFinder statistical algorithms. The results showed that
EF1α
,
ACT
and
SAND
are suitable reference genes across all samples tested. We recommend the normalization of target gene expression under different experimental conditions using these three genes together. Validation of selected reference genes was achieved by assessing the relative expression levels of
P5CS
and
GI
. This work identified the appropriate reference genes for transcript normalization in buffalobur, which will be helpful in future genetic studies of this invasive weed.