Historical data have demonstrated an underrepresentation of females and minorities in science, technology, engineering, and mathematics (STEM) professions. The purpose of the study considered the variables of gender and ethnicity collectively in relationship to tenth grade Hispanic females' perception of their self-efficacy in science. The correlation of science self-efficacy to science academic achievement was also studied. Possible interventions for use with female Hispanic minority populations might help increase participation in STEM field preparation during the high school career. A population of 272 students was chosen through convenience sampling methods, including 80 Hispanic females. Students were administered a 27-item questionnaire taken directly from the Smist (1993) Science Self-efficacy Questionnaire (SSEQ). Three science self-efficacy factors were successfully extracted and included Academic Engagement Self-efficacy (M=42.57), Laboratory Self-efficacy (M=25.44), and Biology Self-efficacy (M=19.35). Each factor showed a significant positive correlation (p<.01) to each of the other two factors. ANOVA procedures compared all female subgroups in their science self-efficacy perceptions. Asian/Pacific and Native American females had higher self-efficacy mean scores as compared to White, Black and Hispanic females on all three extracted science self-efficacy factors. Asian/Pacific females had the highest mean scores. No statistically significant correlations were found between science-self-efficacy and a measure of science achievement. Two high-ability and two low-ability Hispanic females were randomly chosen to participate in a brief structured interview. Three general themes emerged. Classroom Variables, Outside School Variables, and Personal Variables were subsequently divided into sub themes influenced by participants' views of science, It was concluded that Hispanic female science self-efficacy was among the subgroups which self-scored the lowest. Asian/Pacific and Native American females fared better than White, Black, and Hispanic female counterparts respectively. Triangulation of interview and quantitative data showed that classroom factors, specifically academic engagement, influenced participant perceptions of science self efficacy the greatest. Suggested further studies on the impact of science self-efficacy and science achievement are discussed. Information gleaned from the continued study of science self-efficacy may influence the ability of traditionally underrepresented racial/ethnic females to persist in their science preparation and training in an effort to prevent leaving the STEM pipeline at this crucial juncture.