Because underwater gliders can travel over thousands of kms long for serveral months and measure water properties 3 dimensionally different from general AUVs, they have been received attention from ocean observation and defense area. At this research, we aim to developing and designing an underwater glider weighed about 70 kg, which can be oeprated at real field and handled easily. This paper introduces its design aspects and techniques during developing, especially considering long term and range operation.s research, we aim to developing and designing an underwater glider weighed about 70 kg, which can be oeprated at real field and handled easily. This paper introduces its design aspects and techniques during developing, especially considering long term and range operation.