Production of strawberry (”Fragaria” × ”ananassa” Duch.) using plastic tunnel system is popular in northern Taiwan due to the rainy winter conditions. Although the plastic tunnel system provides shelter for strawberry leaves and fruits from the raining damage, it unavoidably reduces irradiation for energy source of photosynthesis. The negative effect of shading on whole-plant photosynthesis and growth has yet to be documented in strawberries. During winter and spring in Taipei area, the PE plastic tunnel system caused 30% declination of light intensity and led to 30% reduction of whole canopy photosynthesis rate in container-grown 'Toyonoka' strawberries. Consequently, total leaf area decreased by 35% and dry weight by 60% in the late production season in strawberry plants grown in the plastic tunnel, as compared to field-grown plants. The vegetative growth and whole canopy photosynthesis of strawberry plants in the tunnel was severely suppressed by the shading effect from the plastic tunnel. The consequences on yield and fruit quality in commercial strawberry production should be further evaluated.