The Preschool Oral Healthcare Programme (POHP) was introduced in Malaysia by the Ministry of Health in 1984 to provide oral healthcare for 5–6-year-old children. Most of its evaluations were directed towards assessing children’s oral health status. Little emphasis has been placed on assessing the programme feasibility from the perspectives of the oral health personnel. The objective of the study was to explore the facilitators and barriers to the implementation of the POHP using the perspectives of dental therapists (DT) in Selangor state, Malaysia. This study took a qualitative approach using focus group discussion (FGD) as the data collection method. The data were transcribed verbatim followed by thematic analysis using Nvivo software. A total of 13 FGDs had been conducted involving 114 DT. The main facilitators were good dental teamwork, assistance from schools and teachers, sufficient training of DT, adequate support from dental administration, and good cooperation from the children. The main barriers were lack of financial support, manpower, time, inadequate support from preschools and children, language barrier, and accessibility to sugary food and drinks at schools. The study provided important insights regarding the POHP that would be useful for programme improvement through policy changes, workforce training, and enhanced school participation.