Crowding and diastema are common malocclusion conditions that occur due to a discrepancy between tooth size and jaw size. The treatment that can be done is based on the severity of the case. Mild cases of malposition can be treated with removable orthodontic appliances. This article aims to show the analysis how an active plate device with a simple spring was used to treat multiple maxillary diastemas and anterior crowding of the mandible. The patient complained that his upper front teeth gap and his lower teeth were crowded. It does not interfere with the appearance, but sometimes open food is tucked between the front teeth. The patient has never used an orthodontic appliance before. Molar relation: Malocclusion Angle class 1 type dental with mild individual tooth malposition. Twenty-two treatment visits were performed. Treatment was carried out using an active plate with a simple spring on teeth 13, interdental 31-41, and 43; retentive components using Adam Clamer on teeth 16, 26, 36, and 46; long labial arch with U loops on the right and left permanent 1st premolar teeth. In the 22nd control, the results showed that teeth 11, 21, and 43 malpositions were corrected, and the diastema was closed on tooth 14 against 13 and tooth 21 against 22. In addition, the width of the diastema on interdental 13-12, 12-11, and 22-23 was reduced to 0.05 mm. An active plate with a simple spring can correct diastema and mild crowding of the anterior teeth