Grain boundary character distribution of commercially pure Zr (Zr702) was studied by experiment in conjunction with the Monte-Carlo computer simulation. With the application of equal channel angular pressing (ECAP) the grain size was efficiently reduced to 310nm. A strong basal texture developed in the as-deformed specimen with a microstructure consisting of mostly high angle grain boundaries. The crystal texture and the grain boundary characteristics were insensitive to the subsequent heat treatment at 800degreesC. This phenomenon, confirmed by experiment and by the computer simulation as well, was attributed to the high mobility of mostly high angle grain boundaries formed during ECAP and subsequent recrystallization.