A medical ventilator capable of switching air types includes a case and a rotary valve arranged on the case. The case includes a first air-intake channel, and a second air-intake channel. An air-storage space is formed inside the case. The rotary valve can be rotated between a first position for blocking a communication between the first air-intake channel and the air-storage space and a second position for blocking a communication between the second air-intake channel and the air-storage space. Accordingly, the first air-intake channel and the second air-intake channel can be respectively utilized for being communicated with an oxygen source and an air source. The user can switch the rotary valve between the first position and the second position only, to switch output air of the ventilator to air or oxygen according to the requirement.一種可切換供氣種類之呼吸器，係將一旋轉閥設於一機殼，該機殼具有一第一進氣通道及一第二進氣通道，並形成有一儲氣空間，該旋轉閥可於一阻擋該第一進氣通道與該儲氣空間連通之第一位置及一阻擋該第二進氣通道與該儲氣空間連通之第二位置之間轉動；藉此，該第一、第二進氣通道可分別用以連通至一氧氣源及一空氣源，使用者只要將該旋轉閥切換至該第一位置或第二位置，即可依照需求將該呼吸器所輸出之氣體切換為空氣或氧氣。
