Temperature is a parameter increasingly monitored in wind turbine systems. This paper details a potential temperature monitoring technique for use on shaft couplings. Such condition monitoring methods aid fault detection in other areas of wind turbines. However, application to shaft couplings has not previously been widely researched.A novel temperature measurement technique is outlined, using an infra-red thermometer which can be applied to online condition monitoring. The method was validated and investigated through real time shaft alignment tests. Different modes of misalignment including offset and angular were investigated. This allowed analysis of the relationship between a change in shaft alignment and a change in temperature. The rate of change was found to be a factor of condition through exploring changes in ambient and operating temperatures. The test rig allowed quantification on a small scale and potential causes and effects of temperature changes are discussed.