Plenas is a municipality in the province of Zaragoza, in the autonomous community of Aragon, Spain. It lies within the Campo de Belchite comarca, a rural area in the Ebro valley region of northeastern Spain.
The municipality is small and sparsely populated. According to the 2004 census carried out by Spain's National Statistics Institute (INE), Plenas had a population of 131 inhabitants.
Like many villages in the Campo de Belchite area, Plenas is a quiet, rural settlement whose character reflects the agricultural traditions of the surrounding comarca. Its small population and location within Zaragoza province place it among the many minor municipalities that make up the Aragonese countryside.