In this work, the flow distributions of 16-, 8-, 4-, 2-channels microreactors with 2-D constructal inlet distributors were measured. The results showed an increase in channel numbers caused a decreasing uniformity of the flow distribution. Both asymmetrical velocity profiles before a bifurcation point and asymmetrical flow resistance after a bifurcation point played an important role on the flow distribution in microchannels. The uniformity of flow distribution showed a trend of firstly increasing and then remaining unchanged with the increase of Re (4 ∼ 680). The pressure drops of microreactors were also investigated and the empirical method is in the acceptable range for estimating the energy consumption. Extending the channel length after bifurcation point from 124.46 mm to 160.95 mm and incorporating a bypass pressure equalization chamber at bifurcation point could improve the uniformity of flow distribution.