Jansenism wani yunkuri ne na addini wanda ya samo asali a karni na 17 a cikin Cocin Katolika, wanda aka yi wahayi daga koyarwar masanin tauhidin Dutch Cornelius Jansen. Jansenism ya nanata bukatar yin riko da koyarwar Katolika da ɗabi'a sosai, gami da kaddara da zunubi na asali, kuma sun ƙi wasu fannoni na koyarwa da ayyukan cocin, kamar su sha'ani da girmama tsarkaka.Tafiyar ta kasance musamman. mai tasiri a Faransa, inda aka danganta shi da adawa da Jesuits da goyon bayan Gallicanism, ra'ayin cewa cocin Faransa ya kamata ya sami 'yancin kai daga Roma. Cocin Katolika ta yi Allah wadai da Jansenism a matsayin bidi'a a ƙarni na 18, kuma an tsananta wa mabiyanta kuma an danne su. Duk da haka, an ci gaba da jin tasirinsa, musamman a ci gaban addinin Katolika na Faransa da kuma farfaɗo da sha'awar tauhidin St. Augustine.