The lack of sufficient information on the attributes of the secondary vegetation in Tabasco contributes to obscure the importance of these ecosystems in conservation programs and as carbon reservoirs. The present study contributes to fill in the knowledge gaps regarding the magnitude of the existing biomass in fallow lands. In three eco-geographic units, 18 clumps -each consisting of four 10 × 40 m plots- with an inverted Y arrangement were established in secondary forests aged 15, 20, 30, and 100 years, covering a total surface area of 28 800 m2. In each study area, mensuration parameters were taken to determine the plant biomass and the basic structural characteristics. Results showed that younger secondary forests support a higher density of individuals, which are mainly distributed in two diameter classes (2-10 and 10-18 cm, ND) and three height levels (2-7, 7 -12 and 12-17 m). The basal area and biomass did not change proportionally to the age or successional stage. In spite of their variability, these ecosystems have been shown to have a high potential for carbon capture and accumulation in a shorter period compared to the primary vegetation. Therefore, if these abandoned areas continue to grow to advanced successional stages, they will be an alternative strategy for such environmental services as carbon sequestration and biodiversity.