A temperature sensing device measures the temperature of a fluid at selected locations along an IV fluid line. The device is secured to a selected portion of the IV line and includes a temperature sensor for measuring fluid flowing within that line. The device is coupled to a temperature display device to display the measured temperature. The temperature sensing device may include: a housing with a lower cover to engage the line and a temperature sensor; a holder movable along the line and including a temperature sensor; a housing with a lower member including a tip to pierce and measure temperature of fluid within the line; a resilient member with a spiral configuration and a tip to pierce and measure temperature of fluid within the line; a `T`-type fitting including a temperature sensor; or a `Y`-type fitting including a temperature sensor in the form of a needle.