Twenty species of the genus Tetragnatha are recognized to occur in the Neotropical and Mexican Regions. Three new species, T. eberhardi, T. levii and T. paradoxa, are described. Seventeen species, T. boydi, T. caudata, T. cognata, T. confraterna, T. elongata, T. ethodon, T. gertschi, T. guatemalensis, T. jaculator, T. laboriosa, T. mabelae, T. mexicana, T. nitens, T. pallescens, T. pallida, T. sinuosa and T. tenuissima are redescribed and illustrated. T. jaculator is recorded from the Neotropical Region for the first time.