Introduction: Oral sensory problems in Autism Spectrum Disorder (ASD) are mainly due to lack of sensory-motor synchronisation and incomplete neuromuscular development. Direct oral stimulation can play a significant role as a part of oral therapy, because the speech outcome by Speech Therapy (ST) has subjective variation and requires a long period of time. The other oral muscular therapy has lack of specificity and sensitivity. However, the direct oral stimulation in the form of appliance therapy has not yet been investigated. Aim: To explore the precise role of Speech-sensory Appliance (SSA) on speech disorder and associated oral sensory problems in ASD children. Materials and Methods: In this single-arm, Randomised Controlled Trial (RCT), 40 ASD-diagnosed children between the ages of 4 and 11 will be involved. The study participants will be split into two groups of 20 each at random. While the other group will be exposed to SSA+ST therapy, one of the groups will undergo SSA therapy. The speech therapist was unaware of the group of children who received both therapies (blind). Analyses of the results will be conducted utilising voice recordings and Visual Analogue Scales (VAS). Before and after therapy, the voice recording graph will be collected. Parents will be given a short questionnaire as part of the VAS to track any changes in feeding behaviour. Expected Results: SSA therapy that is 3D printed will result in better speaking outcomes and feeding behaviour. Conclusion: If the current study’s hypothesis is confirmed, direct oral stimulation can be employed either alone or in conjunction with ST to improve participants with ASD’s speech outcomes and feeding behaviour.