The improved structure of the ultraviolet germicidal lampshade for aquarium comprises an ultraviolet germicidal lamp body, an upper cover portion, a transparent glass tube sleeve and a lower cover portion. The ultraviolet germicidal lamp system is extended with a UV ultraviolet lamp, and the upper edge portion of the upper cover portion can be Inserting the ultraviolet germicidal lamp body, the transparent glass tube is sleeved inside the lower edge surface of the upper cover portion, and the UV ultraviolet lamp that is worn on the upper cover portion can be completely covered to avoid water flow soaking, and the lower cover portion is disposed on the The outer surface of the lower edge of the upper cover portion is designed to have a regular or irregular arrangement such as a wavy shape, an arc shape, a pointed shape, or the like by a structural feature in which the cylindrical surface of the metal cylinder is arranged in a concave-convex manner. a water inlet is formed on the side of the lower end of the lower cover portion, and a water outlet is formed on the side edge of the upper cover portion. When used in combination, the water flows into the flow or air discharged from the outlet through the inlet. The UV-UV lamp can be directly irradiated to have a sterilizing function, and since the cylindrical surface of the metal cylinder is arranged in a concave-convex manner so that the cross-section is like a wavy design, there is a cross inside. By increasing the reflection effect function UV germicidal UV light.一種水族用紫外線殺菌燈罩之改良結構，包括有紫外線殺菌燈體、上蓋部、透明玻璃管套，與下蓋部所組成，該紫外線殺菌燈體係延具有UV紫外線燈，該上蓋部上緣面可穿套該紫外線殺菌燈體，該透明玻璃管套設於該上蓋部下緣面內部而可將該套穿於上蓋部之UV紫外線燈完整套住以避免水流浸泡到，該下蓋部設於該上蓋部下緣面外部，並藉由其上方設有金屬筒部柱面以凹凸相間方式圍置的結構特徵而產生剖面如類似波浪狀、圓弧狀、尖齒狀等規則或不規則排列的設計，搭配該下蓋部下端側面開有水流入口，與該上蓋部側緣面開有水流出口的結構，俾於結合後使用時，水經流入口流入由流出口流出所導出之水流或空氣不但可讓UV紫外線燈直接照射而具殺菌功能，且因為金屬筒部柱面以凹凸相間方式圍置使得剖面如類似波浪狀的設計，形成內部會有交叉倍乘的反射效果以增加UV紫外線燈的殺菌功能。
