The purposes of the study were 1) to investigate the effectiveness of the applied cooperative learning and Polya's problem-solving process on grade 9 students' mathematical problem-solving ability, 2) to compare grade 9 students' learning achievement before and after learning through the applied cooperative learning and Polya's problem-solving process, and 3) to study the students' satisfaction toward learning through the applied cooperative learning and Polya's problem-solving process. The participants were 18 grade 9 students in a Thai secondary school selected by the stratified random sampling method. The instruments were 1) an applied cooperative learning and Polya's problem-solving process learning management, 2) a mathematical problem-solving test, 3) a learning achievement test, and 4) a satisfaction questionnaire. The data were analyzed using percentage, mean score, standard deviation, one-sample t-test, paired-samples t-test, and effectiveness test with the criteria of 70. The results of the study indicate that 1) the learning management designed using the applied cooperative learning and Polya's problem-solving process was effective in developing students' mathematic problem-solving ability, 2) the students' learning achievement of surface area and volume in the posttest was higher, and 3) the students were satisfied with learning with the lesson plans using the applied cooperative learning and Polya's problem-solving process. The results could be applied in both mathematics classrooms and similar research study area of mathematics instruction.