This paper describes the findings of a numerical and experimental study on the heat transfer coefficient and pressure drop in micro-lattice blocks fabricated by selective laser metal melting and subjected to forced air convection. In particular, the influence of the unit-cell topology on the thermofluid performance of the lattice structure is examined in detail. In the present numerical study, five lattice block designs (BCC, BCCZ, FCC, FCCZ and F2BCC) are considered for investigation. Regarding effective thermal conductivity, the FCC and FCCZ lattices offer the best performance among the various lattices. In terms of heat transfer capacity per unit mass, the BCC and BCCZ lattices exhibit superior characteristics relative to the other lattices. Also, F2BCC lattice offers the lowest pressure loss for a given relative density. In addition, it is found that the heat transfer coefficients obtained by experiment lie between two numerical results having different strut diameter, which is due to the fact that the equivalent strut diameter in the as-manufactured samples is greater, due to the present of additional metal particles fused onto the surfaces of some struts. Moreover, it is found from our experimental investigation that the heat transfer coefficient h for the BCCZ is approximately 1.3 times higher than that for the BCC lattice for the same pressure loss.