Abstract A set of test instrument about Problem Solving Skill has been created in essay form in concept of simple tool for junior high school. The research objective is to construct a test Problem Solving Skill and obtain information relating application results. The research method used is descriptive research. Data gathered from the results of the test and research notes. Test of validity using professional judgment and statistical validity. Reliability testing using Cronbach Alpha. The results of the study informed that the construction of the validity of the tests qualify as much as 71%, which is higher (25%), sufficient (33%), and low (13%). Reliability of the instrument has enough categories (0.431). Profile of Problem Solving Skill measured identify the problem (79.17%), define and represent the problem (62.01%), explore possible strategies (69.61%), act on the strategies (58.33%), and look back and Evaluate the effect of our activities (51.47%). The conclusions are construction of test instrument still needs improvement, especially about the aspects of Problem Solving Skill. The ability of students in terms of identifying the problem better than the performance capability by evaluating problems. Keywords: Problem Solving Skill, Concept of Simple Tool. Abstrak Telah dibuat satu set instrumen tes Problem Solving Skill bentuk uraian dalam materi pesawat sederhana untuk level SMP. Tujuan penelitian adalah mengontruksi rancangan tes Problem Solving Skill dan memperoleh informasi hasil-hasil penerapannya. Metode penelitian yang digunakan yaitu penelitian deskriptif. Data dikumpulkan dari hasil tes dan catatan penelitian. Pengujian validitas menggunakan professional judgement dan validitas statistik. Pengujian reliabilitas menggunakan Cronbach Alpha. Hasil penelitian menginformasikan bahwa konstruksi tes yang memenuhi syarat validitas sebanyak 71%, yaitu tinggi (25%), cukup (33%), dan rendah (13%). Reliabilitas berkatagori cukup (0,431). Profil Problem Solving Skill yang terukur adalah identify the problem (79,17%), define and represent the problem (62,01%), explore possible strategies (69,61%), act on the strategies (58,33%), dan look back and evaluate the effect of our activities (51,47%). Kesimpulan yang diperoleh, yaitu pertama konstruksi instrumen tes masih perlu perbaikan terutama yang berkaitan dengan aspek-aspek yang ada pada Problem Solving Skill. Kedua, kemampuan siswa dalam hal mengidentifikasi masalah lebih baik daripada capaian kemampuan cara mengevaluasi masalah yang muncul. Kata-kata kunci: Problem Solving Skill, Materi Pesawat Sederhana.