Effect of second phase on ductility of Al-Ti-Cr alloys was investigated by compression test at R.T. and 77K. The alloy composition was selected within $Ll_2$ single phase and two-phase field which contains each of six second phases by two different amount, few % and about 20%, in the Al-Ti-Cr phase diagram. Button ingots of Al-Ti-Cr alloys were prepared by arc melting to investigate their microstructure and compressive ductility. In general, homogenization of arc melted ingots substantially reduces the amount of second phases but introduces extensive pore. However, no residual pore was observed in higher Cr content alloys. Environmental effect on ductility of Al-Ti-Cr alloys was investigated through compression test conducted at different strain rates($1.2\times10^{-4}s^{-1}$ and $1.2\times10^{-2}s^{-1}$). Two-phase alloys were more affected by environmental embrittlement than $Ll_2$ single phase alloys. Compared to $Ll_2$ single phase, two-phase alloys consisting of 20% second phase showed relatively high yield strength and poor ductility. However, the alloy consisting of 20% $Cr_2Al$ showed good ductility as well as high yield strength.
