We present a genome assembly from an individual male Apamea sordens (the Rustic Shoulder-knot; Arthropoda; Insecta; Lepidoptera; Noctuidae). The genome sequence is 614 megabases in span. The whole assembly is scaffolded into 31 chromosomal pseudomolecules, including the assembled Z sex chromosome. The mitochondrial genome has also been assembled and is 16.3 kilobases in length.