Planning and implementing a lesson is not an easy thing to do. Also, it is not an easy task to find good and relevant context for all mathematical concepts. The results of the International PIAAC and PISA studies show that people and students have low competence when solving problems with context. The formulation of problem of this study is how to design mathematical Modeling tasks for learning mathematics using water faucet damage contexts in vocational high school which is valid?. This research used development research methods developed by Akker, Gravemeijer, McKenney and Nieveen. This development research consists of 3 stages, namely analysis, design and evaluation. In the analysis step, student analysis, curriculum, mathematical modeling and real-world problems are conducted. The second step, design and product. The last step, the researcher used a formative evaluation design consisting of selfevaluation, one-to-one, expert review, small group, and field tests. After being collected, the data are analyzed using descriptive analysis method: (1) walk through, analysis based on expert comments in expert review to get mathematical modeling tasks for mathematical modeling learning which was valid; (2) Analyze the results of the review in one to one. Based on two expert validation, i.e. an expert in numeracy (education) and an expert in pure mathematics and applications and modeling. Mathematician commented that the problem of modeling was good and challenging but needed a little revision, such as Mathematician commented that there was water that did not enter the tub because it dripped on the ceramics. Expert of numeration commented that The problem is based on a very good idea, and I really like the way it is set up in an Indonesian bathroom, a nice cultural influence. Students' answers show they could not make assumptions but could make variables. Student comment that these modeling tasks are difficult but good or interesting. So, it was obtained mathematical modeling tasks using water faucet damage was valid for learning mathematics. Based on this research, it is recommended to use modeling tasks using water faucet damage in mathematics teaching and learning.