Ko te Ture o te 3 o Mei 1791, i huaina ko te Ture Whakahaere, he ture i whakaaetia e te Sejm Nui ("Four-Year Sejm", i hui i te 1788-92) mo te Polish-Lithuanian Commonwealth, he kingitanga takirua e uru ana ki te Karauna o te Kingi o Poland me te Grand Duchy o Lithuania. I hangaia te Ture hei whakatika i ngā hapa tōrangapū o te Commonwealth. I mua i te wa o te whakaoho mo te whakaurunga o nga whakahoutanga, ka timata me te Sejm o te 1764
me te pōtitanga i taua tau o Stanisław August Poniatowski, te kingi whakamutunga o te Commonwealth.