。
She didn't lend an ear to what he said.
Literal
She [topic-は] his [genitive-の] saying thing [to-に] ear [object-を] didn't-lend.
耳を貸す ('lend an ear, listen to') is a shared idiom across English and Japanese — both use the same 'lending an ear' metaphor. Negation 耳を貸さない gives 'doesn't listen, refuses to listen.' The thing not listened to takes に — ~に耳を貸す. A useful expression for situations where someone is ignoring advice, criticism, or appeals.