The study will be conducted in crossover trial, with two 12-weeks periods separated by a Wash-out period of at least one month. According to randomization ,patients will be provided with either Diabeloop system or the usual system.

Patients will be trained for the use of blood glucose meter, of external Insulin Pump and Diabeloop system.

In both treatment periods, the same blood glucose meter will be used throughout the duration of the study.

In two centers (Centre Hospitalier Sud-Francilien and Grenoble), a pre-study will be performed during four weeks to improve the efficacy of Diabeloop system with data collection, to test the manual settings by health care providers and patients and to check the good-working of the follow-up platform.

Inclusion Criteria:

• Type 1 diabetic patient for at least two years
• Patient treated by external insulin pump for at least 6 months
• Patient with HbA1c ≤ 10%; dosage of less than 4 months done in analysis laboratory medical or equivalent.
• Patient requiring a daily dose of insulin ≤ 50 units
• Patient domiciled in an area with Global System for Mobile Communication (GSM)
• Not isolated patient, not living alone, or having a person "resource" living nearby and having a phone and the key of its place of residence
• Patient not envisaging a journey outside France during the "closed-loop" period
• Patient aged over 18 years
• Patient affiliated to Social Security
• Patient who agreed to participate in the study and who signed an informed consent

Exclusion Criteria:

• Patient with any serious illness that may impair study participation
• Patient having a treatment known to have a significant interference on the glycemia.
• Patient enjoying a measure of legal protection
• Pregnant woman or likely to be