The objective of this study was to evaluate the potential of Commelina diffusa L. as a ruminant feed. Commelina diffusa belongs to the Commelinaceae family, a family of plants that is generally poorly investigated with respect to ruminant nutrition. The species was evaluated in terms of its chemical composition, and through the in sacco technique, its rumen degradation characteristics. Rumen degradability was determined in three mature female goats, each fitted with a permanent rumen cannula. Commelina diffusa contained 177 g crude protein (CP)/kg dry matter (DM) and its CP had a rumen degradability of 74.1 ± 2.7%. Most of the DM and organic matter (OM) were lost during the first 36 h of incubation and the cell wall components after 48 h of incubation. Maximum (120 h) DM, OM, neutral and acid detergent fibre, hemicellulose and cellulose disappearances from the bags incubated in the rumen were 66.3, 57.8, 55.6, 55.2, 56.7 and 44.3%, respectively. Rumen degradation of DM and OM was correlated (r2 = 0.66), but significantly different. It is concluded that, from a nutritional point of view, C. diffusa compares well with many commonly used fodder crops and could be used as protein source for ruminants on smallholder farms.