Existing literature is incomprehensive on the factors influencing the choice of subject specialisation by students at teacher training institutions in Eswatini. Thus, there was a need to investigate factors influencing the choice of subject specialisation by students enrolled for Primary Teachers’ Diploma (PTD) in Eswatini. The study was a descriptive survey research triangulating a desk review, modified Delphi technique and a survey questionnaire in data collection. The study was also a census of the 2012/2013 third year PTD students (N= 351) from three teacher training institutions. The instrument was validated by teacher educators involved in the programme who were also used during the Delphi process. It was found to be 83% reliable. The data were analysed using descriptive statistics and non-parametric statistics. The main findings of the study revealed that student interest and attitudes; and impressions were major factors in choosing the subject specialisation.