Sidayu
{{Expand Indonesian|Sidayu, Gresik|date=June 2020}}
{{Infobox settlement
| name = Sidayu
| settlement_type = District (kecamatan)
| subdivision_type = Country
| subdivision_name = {{flag|Indonesia}}
| subdivision_type1 = Province
| subdivision_name1 = East Java
| subdivision_type2 = Regency
| subdivision_name2 = Gresik
| population_total = 37871
| population_as_of = 2010
| area_total_km2 = 47.13
| parts_type = Villages/Sub-districts
| parts_style = para
| p1 = 21
| population_density_km2 = auto
}}
Sidayu is a sub-district (id:kecamatan) in Gresik Regency, Indonesia.{{Cite web|title=District: Sidayu {{!}} Indonesia Postal Code ✉️|url=https://idn.youbianku.com/district/Sidayu|website=idn.youbianku.com|access-date=2020-05-15}} The district lays to the north of Gresik. The district has a long history associated with merchants.{{Cite book|last=Rigg|first=Jonathan|url=https://books.google.com/books?id=kuo-AAAAcAAJ&q=Sidayu+district&pg=PA446|title=A Dictionary of the Sunda Language of Java|date=1862|publisher=Lange|language=en}}