The present invention provides an air purifier capable of uniformly and efficiently purifying air taken in by a photocatalytic reaction by a photocatalyst irradiated with ultraviolet rays from an ultraviolet LED light source. A plurality of LED light sources 12 are arranged in a substantially triangular shape with one end portion 11a side of a substrate member 11 as a base side and the other end portion 11b side as a vertex side, and one or a plurality of adjacent ones in the vertical direction. The LED light sources 12 are arranged so as not to be arranged in a straight line in the vertical direction to form an LED mounting substrate 10, and the LED mounting substrate 10 and a photocatalyst sheet 20 in which a photocatalyst is supported on a sheet member are formed. Oppositely arranged in the channel case 2. [Selection] Figure 1【課題】取り込んだ空気を紫外ＬＥＤ光源からの紫外線を照射した光触媒による光触媒反応によってムラなく均一に且つ効率的に清浄化することができる空気清浄器を提供することにある。【解決手段】複数のＬＥＤ光源１２を基板部材１１の一端部１１ａ側を底辺側とし他端部１１ｂ側を頂点側とする略三角形状に配置すると共に、縦方向に隣接する１個あるいは複数個のＬＥＤ光源１２同士をいずれも互いに縦方向に直線状に並ばないように配置してＬＥＤ実装基板１０を形成し、このＬＥＤ実装基板１０とシート部材に光触媒が担持されてなる光触媒シート２０とを流路ケース２内に対向配置した。【選択図】図１
