TlInGaAs/InP double heterostructures (DHs) were grown on (100) InP substrates by gas source MBE. The photoluminescence (PL) peak energy and its variation with temperature decreased with increasing Tl composition. For the DH with a Tl composition of 13%, the PL peak energy varied only slightly with temperature (-0.03 meV/K). This value corresponds to a wavelength variation of 0.04 nm/K and is much smaller than that of the lasing wavelength of InGaAsP/InP distributed feedback laser diodes (0.1 nm/K). The TiInGaAs/InP light emitting diodes were also fabricated and the similar small temperature variation for the electroluminescence peak energy was observed. The results are a great first step to realize the laser diodes with temperature insensitive lasing wavelength characteristics, which are important in the wavelength division multiplexing (WDM) optical fiber communication systems.