This paper presents an experimental investigation on the local surface heat-transfer coefficient on the shell side of a longitudinal-flow shell-and-tube heat exchanger with a multiparallel channel (MPC) inlet and outlet. Under the conditions of with or without a fluid flow distributor (FDB) in the inlet region of the heat exchanger, some characteristics (such as the local Nussult number (Nu) distribution, local-mean No distribution, overall heat-transfer performance, and pressure drop) were investigated. The investigation results reveal the distribution of the local surface Nu value in the inlet region, and they give a reasonable mechanism analysis. It was suggested that not only the uniformity of both the fluid flow and the local Nu distribution was effectively improved by FDBs, but also that the global heat-transfer surface No value of the heat exchanger was enhanced by more than 10% with the pressure drop increasing slightly by FDBs.