This study investigated the effects of early field experiences on preservice teachers' teacher efficacy (TE) beliefs, a cognitive process in which teachers construct beliefs about their capacity to help students learn. The study also explored the effects of early field experiences on preservice teachers' TE beliefs in terms of their early field experience ratings, their perceived cooperating teachers' TE beliefs, and their teaching anxiety levels. Participants were 52 sophomore-level undergraduate students majoring in elementary and early childhood education, all of whom were randomly assigned to two local elementary schools. Participants made a total of six field experience trips. Data were collected before and after the early field experience. Data collection involved the Teacher Efficacy Scale, the Teaching Anxiety Scale, the Perceived Cooperating Teachers' Efficacy Scale, and the Field Experience Rating scale. Results indicated that after early field experiences, general teaching efficacy (GTE) was significantly lower, whereas personal TE was significantly higher. There was a relationship between student teachers' TE beliefs and their early field experience settings, their perceived cooperating teachers' TE beliefs, and their teaching anxiety. Respondents with higher perceived cooperating teachers' TE had higher GTE. Respondents with high teaching anxiety had significantly lower personal TE. (Contains 13 references.) (SM)