Semakin pesatnya perkembangan teknologi, membuat lahirnya perangkat lunak pada sistem komputer atau yang sering disebut software menjadi semakin banyak dan bervariasi. Sesuai dengan fungsinya sebagai alat bantu, software harus memiliki kemampuan yang memudahkan pengguna untuk menyelesaikan tugasnya sehingga menjadi lebih efisien dan efektif. Usability testing dilakukan untuk mengetahui sejauh mana produk dapat digunakan oleh konsumen untuk mencapai tujuan tertentu. Dalam penelitian ini, akan digunakan software statistik Minitab, namun hanya pada pengaplikasian peta kendali p. Untuk mengukur tingkat usability dari software Minitab maka ditentukan lima dimensi yaitu learnability, efficiency, error, memorability, dan satisfaction (Nielsen, 2003 dan ISO 9241). Sebelum dilakukan penelitian, dibuat modul tahap-tahap penggunaan software Minitab pada pengaplikasian peta kendali p dan juga soal-soal pre-test dan post test. Eskperimen ini dilakukan dua kali, yang pertama responden menyelesaikan soal pre-test dan yang kedua responden menyelesaikan soal posttest. Saat melakukan penelitian, akan diukur indikator-indikator dari setiap dimensi. Contohnya, dalam mengukur dimensi learnability indikatornya adalah nilai pre-test, dimensi efficiency diukur berdasarkan waktu penyelesaian pre-test. Selain itu, dimensi error diukur berdasarkan jumlah kesalahan pre-test dan dimensi memorability diukur berdasarkan perbandingan jumlah kesalahan pada saat pre-test dan post-test. Sedangkan dimensi satisfaction akan diukur berdasarkan kuesioner yang disebar ke responden. Setelah itu, data tersebut akan diolah serta dinormalisasi untuk mengetahui nilai usability-nya. Dimensi learnability, error, dan memorability memiliki nilai 0,98; 0,96; dan 0,95 yang berarti tingkat usability-nya sangat baik. Sedangkan dimensi efficiency dan satisfaction memiliki nilai 0,70 dan 0,79 yang berarti tingkat usability-nya baik. Berdasarkan hasil tiap dimensi, maka diketahui tingkat usability software Minitab pada pengaplikasian peta kendali p yaitu sangat baik dengan nilai rata-rata sebesar 0,87. / The developments of technology make an invention in computer system, named software is increasing and varies. In accordance with its function as a tool, software must have an ability to facilitate users in finishing their task, so that it becomes more efficient and effective. Usability testing is performed to determine how far products can be used by consumers to achieve goals. This research will use Minitab Statistical Software, because Minitab is frequently used in lecture. Therefore, this research will carry out experiments using Minitab software, but only on p-chart application. To measure usability level of the Minitab, it will be determined the five dimensions. The dimensions are learnability, efficiency, errors, memorability, and satisfaction (Nielsen, 2003 and ISO 9241). Before the research, made module that shows steps in using Minitab on p-chart application and pre and post test questions. This research was divided by two parts to measure each indicator from those dimensions, the first one is pre-test and the second one is post test. Every dimensions have their own indicators, like learnability is measured based on pre-test score, efficiency is measured based on pre-test completion time and pre-test repair time, error is measured based on the number of pre-test error, and memorability is measured based on the comparison between number of post-test error with number of pre-test error. In addition, satisfaction is measured based on questionnaires which are distributed to the respondents. After that, data will be processed and normalized to know the value of usability. Learnability, error, and memorability have value of 0.98; 0.96; and 0.95 which mean the usability level is very good. While efficiency and satisfaction have value of 0.70 and 0.79 which mean the usability level is good. Based on the value of those dimensions, it’s known the usability level of Minitab Software on p-chart application is very good, with an average value of 0.87.