Air-side forced convective heat transfer of a plate fin-tube heat exchanger is investigated by experimental measurement and numerical computation. The heat exchanger consists of staggered arrangement of refrigerant pipes of 10.2 m diameter and the pitch of fins is 3.5 m. In the experimental study, the forced convective heat transfer is measured at Reynolds number of 1082, 1397, 1486, 1591 and 1649 based on diameter of refrigerant piping and mean velocity. Average Nusselt number for the convective heat transfer coefficient is also computed for the same Reynolds number by commercial software of STAR-CD with standard $k-{varepsilon}$ turbulent model. It is found that the relative errors of average Nusselt numbers between experimental and numerical data are less than 6 percentage in Reynolds number of $1082{sim}1649$. The errors between experiment and other correlations are ranged from 7% to 32.4%. But the correlation of Kim at al is closest to the experimental data within 7% of the relative error.