0.3% of the population in Tulungagung Regency is Catholic.

The Catholic population in Tulungagung Regency, as of December 31, 2023, was recorded at 3,069 individuals. Compared to the previous year, the number of Catholic residents in the regency/city decreased by 4,873 individuals.

According to data from the Directorate General of Population and Civil Registration (Ditjen Dukcapil) of the Ministry of Home Affairs, the proportion of Catholics in this regency/city reached 0.3 percent of the total population in 2024, which numbered 1.14 million.

Based on the distribution across the population of each region in East Java, the proportion of Catholic residents in Tulungagung Regency ranks 14th.

The following is a list of the population of East Java by religion in 2023:
* Islam 1,118,276 (98.39%)
* Protestant 12,230 (1.08%)
* Catholic 3,069 (0.27%)
* Buddhist 832 (0.07%)
* Hindu 140 (0.01%)
* Indigenous Beliefs 140 (0.01%)
* Confucian 16 (0.0%)

Compared to other regions in East Java, the Catholic population in this regency/city ranks 14th out of 38 regencies/cities in East Java province.

Other areas with the largest number of Catholic adherents in East Java province are: Surabaya City (115,110), Malang City (30,705), Sidoarjo Regency (23,237), Malang Regency (13,611), Blitar Regency (10,147), Jember Regency (8,246), Kediri Regency (6,767), Kediri City (6,129), Madiun City (5,663), and Blitar City (5,215).