An ultrasound probe, a device transmitting ultrasound waves on the skin of a patient for medical imaging, needs to be ergonomically designed. An ergonomically designed ultrasound probe can improve convenience, muscular efficiency, performance, and satisfaction, contributing to its usability and prevention of work-related musculoskeletal disorders of sonographers. The present study was intended to develop a protocol which identifies design factors of an ultrasound probe and evaluate an ultrasound probe design using both objective and subjective methods for better usability. The proposed ergonomic evaluation protocol of ultrasound probe design consists of four steps: (1) analysis of usage characteristics, (2) analysis of design characteristics, (3) experimentation for ergonomic evaluation, (4) analysis of experiment results. First, in the usage characteristics analysis step the physical user interface (PUI) between an ultrasound probe and a user is identified by analyzing ultrasound scanning tasks and environments. Second, in the design characteristics analysis step the probe design characteristics is identified by the following subsequent analysis steps: S1. Definition of design dimensions such as length, breadth, thickness, angle, radius, and circumference, S2. Classification of design dimensions into anthropometric factor, biomechanical factor, and affective factor, S3. Importance assessment of design dimensions to determine which dimensions need to be considered with priority in ergonomic design and evaluation, and S4. Measurement of major design dimensions to benchmark the characteristics of probe designs. Third, in the ergonomic evaluation step an ergonomic evaluation protocol is established using objective and subjective evaluation methods and then usability testing of ultrasound probe designs is conducted. Lastly, in the experiment result analysis step the results of ergonomic evaluation results are analyzed and desirable design features of an ultrasound probe are identified based on the results of design dimension measurement and those of motion, EMG, grip posture, satisfaction, and/or debriefing. The proposed ergonomic protocol of ultrasound probe design and evaluation was applied to linear array probe in the present study. The design characteristics of linear array probe were identified by conducting the usage characteristics analysis, design characteristics analysis, and existing probe design benchmarking. Then, desirable design features of linear array probe were identified by comprehensive evaluation of motion, EMG, grip posture, and subjective satisfaction. The proposed ergonomic evaluation protocol of ultrasound probe design can be utilized to design and evaluate a hand-held handle (e.g., vacuum cleaner handle) requiring intensive manipulation of the handle in grip.