A capsule endoscope for observing the conditions inside a patient's digestive tract system includes a capsular housing, a substrate, and a plurality of metal-insert molded contacts. The capsular housing defines a sealed inner space and has an outer surface. The substrate is arranged in the sealed inner space of the capsular housing and is mounted with at least an electronic element provided thereon. The metal-insert molded contacts are embedded in the capsular housing at predetermined positions thereof and each includes a contact base and an exposed contact portion formed on the contact base. The contact bases each have a connecting section extended into the sealed inner space of the capsular housing to electrically connect to the substrate. The exposed contact portions each have a front surface exposed from the outer surface of the capsular housing for contacting with a signal contact correspondingly provided on a capsule holder that holds the capsular housing thereto.