Santa Eulália de Arnoso is an ancient parish portuguese do county de Vila Nova de Famalicão, with an area of 2.68 km² and 1,111 inhabitants (2011)[1]. Its population density was 414.6 inhab/km².
It was joined to the parishes of Santa Maria de Arnoso and Sezures, forming a Union of Parishes of Arnoso (Santa Maria and Santa Eulália) and Sezures with headquarters in Santa Maria de Arnoso.