As a major opportunistic pathogen,
Pseudomonas aeruginosa
can produce various virulence factors and form biofilms. These processes are controlled by the quorum sensing (QS) system. Sodium new houttuyfonate (SNH) is an adduct of houttuyfonate, the main component of the common Chinese medicine plant Houttuynia cordata, which has antibacterial and anti-inflammatory effects. We evaluated the effect of SNH on
P. aeruginosa
biofilms, virulence factors, and transcription. Transcriptome analysis showed that the key
rhlI
and
pqsA
genes of the
P. aeruginosa
QS system were down-regulated after SNH treatment. SNH reduces proteases and pyocyanin production and inhibits biofilm formation by regulating the
P. aeruginosa
QS system. SNH also changes the expression of genes related to virulence factors and biofilms (
lasA, lasB, lecA, phzM, pqsA
, and
pilG
). These results suggested that the mechanism of SNH against
P. aeruginosa
by affecting the expression of biofilm and virulence factors controlled by quorum sensing.