By using ground-based, portable light detection and ranging (LIDAR) system, we quantified canopy structure of evergreen forests with varying dominance of conifers along elevational gradients on tropical and subtropical mountains (Mount Kinabalu, Borneo and Yakushima Island, Japan). Conifers dominated at higher elevations on both the mountains (Podocarpaceae and Araucariaceae on Kinabalu, and Taxodiaceae and Pinaceae on Yakushima), but conifer dominance also depended on soil/substrate conditions on Kinabalu. Except for lowland forests and a subalpine scrub dominated by small-leaved Leptospermum recurvum (Myrtaceae) on Kinabalu, forests with higher conifer dominance showed more positively skewed canopy height profile: conifer-admixed forests had sparser canopy and denser understory than angiosperm-dominated forests. Forests with sparser canopy showed greater horizontal heterogeneity of canopy surface. Conifers on both mountains are generally shade-intolerant, inferior to angiosperm trees in competition for light under dense canopy. Reduced growth of angiosperm trees (except L. recurvum on Kinabalu) in colder and nutrient-poor environments, which results in sparser canopy, appeared to allow conifers to outcompete angiosperm trees.