Jaldhaka (Bengali: জলঢাকা, Joldhaaka, means covered under water) is an upazila of Nilphamari District in the Division of Rangpur, Bangladesh.

According to the 2011 Census of Bangladesh, Jaldhaka Upazila had 78,994 households and a population of 340,672.

Jaldhaka had a literacy rate (age 7 and over) of 37.89%, compared to the national average of 51.8%, and a sex ratio of 987 females per 1000 males.

[5][6] Par the 2001 Bangladesh census, Jaldhaka had a population of 274736, including 141715 males, 133021 females; Muslim 217944, Hindu 56480, Buddhist 38, Christian 113 and others 361.

The upazila is divided into Jaldhaka Municipality and 11 union parishads namely: Balagram, Dharmapal, Douabari, Golna,Golmunda, Kaimari, Kathali, Khutamara, Mirganj, Shaulmari, and Simulbari.