An apparatus for the measurement of the absorption and magnetic circular dichroism (MCD) spectra of matrix‐isolated high temperature molecules is described. A conventional electromagnet capable of producing fields up to 5500 gauss (0.55 T) is shown to produce high quality MCD spectra. A closed‐cycle helium cryostat is used to provide the variable low temperatures required, while a commercial microcomputer furnishes the wavelength advance, the photoelastic modulator voltage control, and digital signal collection. A pseudodouble beam absorption apparatus provides an absorbance (logI0/I) measurement on the same matrix‐isolated sample used for the MCD measurement, enabling straightforward comparison of the two and facilitating interpretation of any MCDA1andC0terms that are observed. The absorption and MCD spectra of the &ggr;′ and &agr; bands of the diatomic TiO in an argon matrix (14 K) are presented to illustrate the power of the combined absorption/MCD matrix isolation method for the assignment of the excited electronic states of high temperature molecules.