Zoology department is one of the leading departments in Nirmala college. Department of Zoology and Botany started and functioned together in 1953 since the establishment of the college. In 1967, it was bifurcated and an independent department was formed for Pre degree course. Bachelors of zoology model 1 was started in 1982. Later in 2001, M.Sc zoology program specialized in Environmental sciences was commenced. The postgraduate department was recognized as Research centre in 2018.The department is supported by UGC and DST-FIST.

The department facilitates basic and comprehensive approach towards developing skills in students through various field studies in biodiversity and environment. Studies are conducted every year in various wildlife sanctuaries, protected areas etc. which includes field work of 15-30 days in unexplored deep forests. The reports of these studies are accepted by Department of forests, Government of Kerala for setting their future plans of conservation and protection of plants and animals. This experience encourages students towards research and also provides them the thirst for working towards environmental conservation. The faculty extends mentoring to students, in pursuing their academic goals in minor research project, in higher education and also to solve personal problems. The department offers an open course on Public health and Nutrition for the students in fifth semester from other discipline such as arts, commerce, computer science, science, etc. The department also conducts a certificate course on wild life biology.

In order to develop extracurricular skills among students, the department organises various events such as Quiz, poster and speech competitions. The chat with scientist programme, helps the students to interact with invited eminent scientists from all over India and abroad. The alumni lecture includes a talk and discussion of prominent alumni of this department from all over India and outside with students. The faculty also focuses on developing diverse skills among students, along with regularity, punctuality, participation and team spirit in various activities and celebrations such as World environment day, Ozone day, Wetland day, Aids day, Societal festivals etc… There are endowment lectures and many cash awards sponsored by retired faculties of our department.The department museum displays various rare animal specimens, skeletons and skulls for osteological studies.Postgraduate and Research department of Zoology has adequate facilities to conduct various Research Programmes. Full time and part time researchers are working here for their Ph.D programmes.