A model for the electronic state of amorphous evaporated arsenic is proposed which is based on the interpretation of its electrical and optical properties. The semiconducting behaviour of amorphous arsenic is analysed using the general density of states model for amorphous semiconductors (localized states at the band edges and in the energy gap). The optical properties are interpreted in agreement with the non-direct transitions model. Taking into account the valence band density of states given by XPS measurements, the authors try to deduce from the experimental optical density of states epsilon 2 omega 2, the profile of the conduction band density of states and the average matrix elements for transitions from initial states of p, s and d character.