The mating behavior of Hyalesthes obsoletus Signoret (Hemiptera: Cixiidae) was studied to determine the role of substrate-borne vibrational signals in partner recognition, pair formation, and courtship. Planthopper vibrational signals were detected from nettle, Urtica dioica L., cuttings by laser vibrometer. Either male or female could initiate the mating sequence that was divided into three sections: recognition, courtship and precopula. The females were the more vibrationally active gender in the recognition stage and males in the courtship and precopula stages. Four distinct syllables constituted the male repertoire and were emitted in different behavioral contexts. The male syllable 1 was used during the recognition duet, as a reply to female pulse trains and it formed, in combination with male syllable 4, the male precopula signal. This latter signal was emitted in the vicinity of a receptive female and accompanied by jerky lateral movements of the body and tapping of the legs to the substrate. Although nonduetting males emitted long trains composed of male syllable 2, males during the courtship phase emitted trains formed mainly by male syllable 3. Female vibrational signals consisted of pulses, emitted either in trains during the recognition phase or as single pulses, in reply to male trains in the courtship stage. In the precopula phase, the females ceased signaling. According to our results, in H. obsoletus the vibrational signals play a major role in stimulating the male search process and in ensuring the female acceptance.