99.1% of the population in Situbondo Regency is Muslim.

The Muslim population in Situbondo Regency as of December 31, 2023, was recorded at 678,030. Compared to the previous year, the number of Muslims in the regency/city increased by 17,328.

According to data from the Directorate General of Population and Civil Registration (Ditjen Dukcapil) of the Ministry of Home Affairs, the proportion of Muslims in this regency/city reached 99.1 percent of the total population in 2023, which numbered 684,340.

Based on the distribution across different regions in East Java, the proportion of Muslims in Situbondo Regency ranks 30th.

The following is a list of the population of East Java by religion in 2023:
* Islam: 678,031 (99.08%)
* Protestant: 4,443 (0.65%)
* Catholic: 1,376 (0.2%)
* Buddhist: 333 (0.05%)
* Hindu: 136 (0.02%)
* Confucian: 21 (0.0%)
* Other Beliefs: 3 (0.0%)

Compared to other regions in East Java, the Muslim population in this regency/city ranks 30th out of 38 regencies/cities in East Java Province.

Other regions with the largest Muslim populations in East Java Province are Malang Regency (2,625,573), Surabaya City (2,589,630), Jember Regency (2,569,636), Sidoarjo Regency (1,913,186), Banyuwangi Regency (1,725,447), Kediri Regency (1,638,549), Pasuruan Regency (1,609,458), Lamongan Regency (1,382,400), Bojonegoro Regency (1,355,806), and Jombang Regency (1,351,098).