Jasienica [jaɕɛˈnit͡sa] is a village in the administrative district of Gmina Tłuszcz, within Wołomin County, Masovian Voivodeship, in east-central Poland.

There are: the railway station (Jasienica Mazowiecka), primary school, middle school, kindergarten, public library, fire brigade, church and park (a remnant of the farm) in the village.

Jasienica is mentioned there as: "Jassenicza", "Jassyenyecz", "Jassyenicza", "Jaszenicza", "Jaszenecz", "Jasiennica", "Jasszenicza", "Jassyeniecz", "Jaschenyecz", "Jasyenyecz", "Jassenycza"," Jaschyenycze", "Jasyenycza", "Yasszyennycza".

At the beginning of the 15th century, Knight Świętosław from Pruszków (from the Pierzchała family) received - in recognition of his contribution to the Mazovian Ducal Court - areas covering Jasienica.

Around 1470, after the death of Świętosław, Jasienica was inherited by one of his sons - probably - Andrew, who having settled in this area took the name Klembowski (also Kłębowski) after - Klembów, the village which also became his property.