Methodologies that analyse the colouration and external appearance of extant species are very useful tools when facing one of the greatest challenges in the palaeoartistic reconstructions of extinct fauna: inferring the colour patterns. Earlier works have applied this methodology, for example, in the reconstruction of the Miocene bovid Tethytragus, proving that the maximum likelihood (ML) analysis to infer ancestral states has promising potential. This study offers a proposal for the reconstruction of the external appearance of Heteroprox moralesi Azanza 1989, an early cervid of the Middle Miocene present in several fossil sites of Central Spain. For the reconstruction of the external appearance, the colour patterns of all the extant species of the family Cervidae were studied with the method of ML analysis, as well as recent works about their phylogeny. The results show the most probable basal colour pattern of the cervids: dark shades on the limbs, dorsal section, and head of the animal, and, in contrast, lighter colours on the neck and perianal region. This basal pattern can be used as a basis for reconstructing colouration and to hypothesise about the external appearance of extinct taxa. Furthermore, the inferred forest habitat of H. moralesi has been taken into consideration in order to adjust the colour pattern, comparing the final results of the analysis performed in this study with that of the pattern observed in extant forest deer as well as with previous works employing this methodology.