A construct validation of a modified version of a teacher efficiency scale was conducted to establish its use with preservice teachers. The scale adapted by A. E. Woolfolk and W. K. Hoy from one constructed by S. Gibson and M. H. Dembo, which contained 12 personal efficacy (PE) and 6 general teaching efficacy (TE) items, was further modified for preservice teachers and administered to 197 education majors from a summer term and 162 education majors from a fall term. Factor analysis and confirmatory factor analysis confirmed the two-factor solution, indicating that the construct is stable to modifications and generalizable to preservice teachers. Confirmatory factor analysis suggests that the model does not fit the data very well. Items on both subscales may need to be revised or eliminated. Five tables present study findings, including data on goodness of fit. (SLD)