Lecture is a common method used in college teaching. Researches are conducted to compare lecture and more active methods in relation to students` performance. This quantitative quasi-experimental research compared the traditional lecture and self-regulating learning method in relation to students` achievement in Biological science. Seventy-eight students were assigned into two groups, with 39 students comprising each group. One group was exposed to traditional teaching while the other group went through the self-regulating learning method of teaching. Initial comparability of the students was based on their pretest scores in Biological Science. Four instrument were used to gather the data that included the students` achievement in biological Science, Self-regulated Learning Strategies, and motivation toward science learning. Other data were collected through focus group interviews and journal entries. Results revealed that students in the traditional method obtained higher mean in the pretest scores, mean in posttest scores, and mean gain scores than students exposed to SRL method. However, there were no significant differences in the mean gain scores of the students exposed to traditional method and SRL model. Lecture method is as effective as the SRL method in the motivation of the students throughout the course. Results further showed that students in both groups were motivated and made use of various strategies in their effort to learn lesson concepts. the varieties of strategies employed by students indicated their self-regulation in learning.