Jan of the Doliwa (died 17 March 1335) was Bishop of Poznaà  from 1324 to 1335.
Little is known about his youth. Prior to his appointment as bishop in Poznaà  he held an office in the Archdiocese of Poznaà Â.
In July 1324, the Poznaà  chapter elected him as another bishop. This election was approved by Janisà Âaw - Archbishop of Gniezno, who made episcopal ordination in the autumn of the same year in Sochaczew. Belonging to the Doliwów family, Jan belonged to the trusted king Wà Âadysà Âaw à Âokietek. In the last months of 1324, Bishop Jan sent food to reinforce Pyzdry, and in June 1325 he belonged to the signatories of a covenant between the king and the West Pomeranian princes against Brandenburg in Nakà Âo. In the same year, Pope John XXII appointed him the conservator of the Owià Âska Cistercian convent, ordering him also to extort Prince Bolesà Âaw III the Spendable to separate the Duchy of Legnica's brother. In February 1326 Jan took part in the synod of the Gniezno metropolis, and in 1329 during à Âokietek's stay at the Poznaà  castle, he belonged to his immediate surroundings.
In March 1331, the bishop, together with the Archbishop of Gniezno and the Cracow bishop, were appointed by the Pope to be the executors of the atonement to be given to the Cheà Âmno bishopric for the losses suffered, and in the event of a refusal they had the right to lay a curse on the order. In July of the same year, the Teutonic invasion ravaged the bishop's estate, destroying Sà Âupca and many villages belonging to the bishop, as well as many other cities in Greater Poland, such as Pyzdry, à Âroda Wielkopolska and Kostrzyn, where churches were burnt. In the Warsaw trial, the court found that the damage, without the temptation of the temples, amounted to 8,200 silver fines. After the death of à Âokietek, the bishop celebrated the coronation mass of Casimir the Great.
During his term of office, the parish church in Krerówo was founded, the estate of the bishops lying in both Greater Poland and Mazovia was merged, and a privilege for millers in the estate of the diocese was issued. The modern bishop calendar of Wà Âocà Âawek described him as a good and generous man, while Jan Dà Âugosz showed him in a negative way, accusing him of extravagance and lack of care for those in need.