In this study, spectral transmittance of signal lights (red, green, and yellow) through each colored lens was measured in other to examine changes in color sense of traffic lights according to color (red, yellow, green, blue, brown, and black) and coloring time (30 sec, 1 min, 5 min, 10 min, 20 min, and 30 min) of plastic tinted lens. The results were as follows ; Spectral transmittance distribution of a red light through lenses having different coloring time for each color (red, yellow, green, blue, brown, and black), study at the lowest value in the range of wave length 580-585 nm through red, yellow, green and blue lenses. The minimum value through brown lens was found at 55 0-600 nm, and at 570-590 nm through black one. Spectral in transmittance distribution of a yellow light through lenses with various coloring time for each color (red, yellow, green, blue, brown and black) stood at the minimum value showed at wavelength 540 nm through red, yellow, and green lenses and at 540- 670 nm through blue, brown, and black lenses. In the examination on spectral transmittance distribution of a green light through lenses having diverse coloring time for each color (red, yellow, green, blue, brown, and black), results appeared similar regardless of color and transmittance was lower less than 15% at the long-wavelength part over 600 nm. The dominant wavelengths of traffic lights according to each tinted lens were calculated as follows. The dominant wavelength of a red light was measured at 665-669 nm in red and yellow lenses, at 669-679 nm in green and blue lenses, at 664-676 nm in brown lens, and at 672-677 nm in black lens. The dominant wavelength of a yellow light showed at 565-558 nm in red lens, at 548-535 nm in yellow lens, at 540-576 nm in green lens, at 549-579 nm in blue lens, at 518 - 575nm in brown lens, and at 566-576 nm in black lens. The dominant wavelength of a green light appeared at 484-472 nm in red lens, at 487-485 nm in yellow lens, at 491-479 nm in green lens, at 490-484 nm in blue lens, at 490- 476 nm in brown lens, and at 483-477 nm in black lens.