The problem of heat transfer for flows in channels with corrugated walls is very complicated. Previously most investigators have focused their attention on studies of forced-convection, single-phase flow, and condensation of pure vapors and vapor gas mixtures. The results of new experimental investigations into heat transfer and pressure drop, for flow boiling in channels with corrugated walls, are discussed. The experimental section was a part of a pack of an industrial plate exchanger, which contained several pressed plates with longitude corrugations located under an angle to flow direction and had many contact points on the heat transfer area. The condensation. method was used for the investigations. The relationship between the heat transfer ratios of the Nusselt number for single-phase flow was obtained. This correlation compares very favorably with the similar relationship obtained for flow bubble boiling in tubes. For correlation of the pressure drop data, the Martinelli-Lockart approach was used, which also correlated well with the results of this study and the results of other investigations. The relationship obtained may be used in calculations for various types of industrial units which have corrugated patterns on their heat transfer surfaces.