Evaluations of higher education programs are increasingly centered on the learner and designed to assess learning effectiveness and core competencies. Although the Taiwan Nursing Accreditation Council (TNAC) has established eight core competencies for college nursing departments, little research has been done to identify the most salient contributors to undergraduate nursing students' perceived competency levels. This paper investigates the influence of student demographic factors and learning experience on students' development in terms of a selected sample of core nursing competencies and then identifies factors that significantly predicts such development. This is a cross-sectional descriptive correlational study. We collected data from a sample of freshmen students currently enrolled in a two-year nursing bachelor degree program at a private vocational university in Taipei, Taiwan. Participants self-assessed abilities in designated core nursing competencies using the Competency Inventory of Nursing Students (CINS). A total of 279 of 290 distributed questionnaires were returned and used in data collection, giving this study a valid return rate of 96.2%. Participants earned a mean CINS score of 5.23 (SD = 0.49). Scale dimensions from highest to lowest mean score rank were: ethics, accountability, caring spirit, communication and cooperation, lifelong learning, general clinical nursing skills, critical thinking, and basic biomedical science. Differentiated analysis revealed that nursing students who expressed a strong interest in nursing, had a clear career plan, held aspirations to pursue higher nursing education, designated "major hospital" as their first workplace of choice, designated a post-college department / workplace preference, had participated in campus activities, were outspoken in classroom discussions and debates, made consistent effort to complete homework assignments and prepare for examinations, and performed relatively strong academically earned CINS scores significantly above the mean. The three factors "having a clear career plan," "having designated a post-college department / workplace preference," and "having participated in campus activities" accounted for 14.4% of variance in subjects' CINS self-rating scores (adjusted R2 = 12.5%). The CINS is an effective instrument for assessing the core professional competencies of nursing students. We recommend that nursing education strategies may be adjusted to enhance student interest in nursing, encourage their developing career plans, and encourage greater participation in campus activities and classroom discussions as a way to improve core professional competencies.