Ecological momentary assessment has been increasingly used in autism studies over the last decade to capture and understand autistic people's behaviours, thoughts, feelings and daily experiences. This systematic review synthesised previous autism ecological momentary assessment studies to learn about the feasibility of ecological momentary assessment with autistic people and derive ideas to optimise the applicability of ecological momentary assessment in autism studies. Five databases (MEDLINE, PsycINFO, Web of Science, EMBASE and CINAHL) were searched, covering the time between January 1990 and October 2024, for studies using ecological momentary assessment with autistic participants. We identified 32 studies with 930 autistic participants. These studies supported the acceptability and feasibility of ecological momentary assessment with young and middle-aged autistic adults with average or above-average intelligence and language skills. Previous researchers and autistic participants in the reviewed literature suggested considering adaptations in the design of sampling schedules, ecological momentary assessment questionnaires and the implementation of incentive strategies, to improve the applicability of ecological momentary assessment with the autistic population. Future ecological momentary assessment studies could address the limitations in the extant literature, for example, lack of evidence from youth and older autistic people and a wider range of study topics.