We have studied the lateral coalescence in microchannel epitaxy (MCE) of InP by LPE. In the present study, we suggest that there are two modes of the coalescence, "one-zipper" and "two-zipper". New patterns of microchannels were designed to realize these two coalescence modes. The coalesced MCE islands were chemically etched and it was found that dislocations were usually generated in the coalesced region when the growth was carried out in the "two-zipper" mode; however, when the growth occurred in the "one-zipper" mode, dislocations were not found in the coalesced region. It is concluded that by conducting the growth in the "one-zipper" mode, the formation of dislocations in the coalesced region can be avoided.