Introduction: Smartphone is one the developing information and communication technology capable of providing information services quickly and accurate so as to make the smart phone as a necessity for all most people today. Some of the positive impact on Smartphone is for students or learners include: accelerate access to information to widely and quickly increase knowledge insight, facilitate in communicating, especially if used to create discussion forum. Extensive use of Smartphone can be associated with physical health related problems, such as pain in the wrist and neck, and it also exposes thumb for intense stresses that may lead to pain and musculoskeletal disorder s of the hand and thumb. Aim of the study: To find the prevalence of de quervain’s tenosynovit is in Smartphone users by using finkelstein test and MRC scale. Method: According to the selection criteria all the subjects were selected for study. Selected subjects explain about study procedure and informed consent obtained from each participant.100 subjects taken. All the subjects had been examined for their thumb muscle strength according to MRC scale and finkelstein test. Data analysis: Data were analysed using Microsoft excel software. Result: Thumb abduction and extension MMT was normal but finkelstain test was positive 33% of prevalence of de quervain’s tenosynovitis. Outcome measure: MRC Scale, Finkelstein test. Conclusion: This study concluded that in smartphone users issue for thumb pain because of long time using smartphonein 100 sample size 33% prevalence of de -quervains tenosynovitis.