A self-ballasted fluorescent lamp includes a luminous tube that is formed in a bent shape with a pair of electrode-side end portions located at a the bottom end of the luminous tube. A cover houses a lighting device for lighting the luminous tube. A base is attached to the bottom end of the cover, and the luminous tube is supported at the top end, of the lamp. The outer diameter of a bulb of the luminous tube 14 ranges from 3 to 8 mm, and the maximum width of the luminous tube, is not greater than 30 mm. The cover is formed so that the proportion of the distance by which the cover extends from the base to the lamp length excluding the base ranges from 0 to 25%, and so that the maximum outer diameter of the cover ranges from 1.0 to 1.5 times the outer diameter of the base.