Human susceptibility to visual discomfort of solid-state lighting was investigated by statistically analyzing for commercial phosphor-converted white light-emitting diodes (PC-WLEDs) with considering optical characteristics such as correlated color temperature (C.C.T., or Tcp), chromaticity, lumen, color rendering Index (C.R.I.) , radiation pattern. These statistic analyses of human factor engineering were based on the surveys and visual measurements among 500 male and female volunteers of ages 18 to 22. The levels of these optical parameters were standardized for indication of the discomfort degree or sensitivity to human visual susceptibility. The results showed that, compared to male human eyes’, female ones could have 20% more sensitive to color rendering on R985 Index, 15% higher in color temperature; however, 30% less sensitive to lumen, and 30% lower recognition ability to radiation pattern. Consequently, it becomes more important for LED manufacturers and solid-state lighting designers to take consideration of such human factor engineering into their products and services.