This study aims to find out: first, the differences in the character concerned about the environment of students between classes taught using problem based learning and classes that do not use a problem-based learning; and secondly, the effect of the application of problem based learning to the character of environmental care. This study was a quasi-experimental research. The study population was all students in fourth grade SawahanBantul, GunungKidul 3 Semanu SD, and SD KemirirejoMagelang. The experimental class, learning carried out with a model problem based learning, while the control class with learning commonly used by teachers. The instrument used was the observation of character care about the environment, with the rating scale. Data analyzed using descriptive statistics to describe the environmental care character,and inferential statistics by using paired sample t test, to test the research hypothesis with a significance level of 5% (α = 0.05). The results showed that: first, there are significantdifferences in the character of environmental care among students taught using problem based learning and students are taught using the usual learning, with sig. 0,000; second, the application of problem based learning had positive and significant effects on the character concerned about the environment, withsig. 0,000.