This corpora-based qualitative study focused on the fillers used by the tertiary education program students in delivering their extemporaneous speech and identifying the function of each filler. The purpose of this study is to analyze the fillers found in the extemporaneous speeches of the students. This study was anchored towards Rose's concept (1998) on the categorization of the Types of fillers, namely: lexicalized and unlexicalized fillers, and supported by Castro's (2009) Functions of Fillers: Opening marker, Information indicator, Fill the time, and Correction Marker. This study was conducted at one of the schools in Tagum City, Davao del Norte, Philippines. The researchers analyzed 20 corpora that were selected based on inclusion criteria. The result showed that the students used 484 fillers in their extemporaneous speeches. The frequency of unlexicalized fillers is observed to be higher among the students compared to lexicalized fillers. Out of 484 fillers, unlexicalized filler "uhm" and lexicalized filler "so” were the most frequent fillers used by the students. Moreover, the most occurring function used is fill the time. Therefore, the presence of fillers found in this study revealed that Tertiary Education Program students used filler words in their speech because they need time to collect their thoughts, lack of confidence, inadequate preparation, poor English vocabulary, and poor English language proficiency. Results of this study can bring further information to the academe to help develop effective communicators who possess strong public speaking abilities essential for success both inside and outside the classroom.