The marsh tit (Poecile palustris) is a passerine bird in the tit family Paridae and genus Poecile, closely related to the willow, Père David's and Songar tits. It is small (around 12 cm long and weighing 12 g) with a black crown and nape, pale cheeks, brown back and greyish-brown wings and tail. Between 8 and 11 subspecies are recognised.