Vehicle lighting device and vehicle lamp

A vehicle lighting device comprising:

• a socket;
• a substrate provided on one end side of the socket;
• at least one light emitting element provided on the substrate;
• a frame part that has a frame shape, is provided on the substrate, and surrounds the light emitting element;
• a sealing part that is provided on an inner side of the frame part and covers the light emitting element;
• and
• a lens that is provided on the sealing part and comprises an optical part into which a light emitted from the light emitting element enters, wherein
• the optical part comprises a first portion from which the light entered is emitted,
• the first portion protrudes to a side opposite to a sealing part side, and
• a contour of the first portion is a substantially rectangular shape as viewed from a direction along a central axis of the optical part, wherein
• a lateral surface of the first portion is only a curved surface that protrudes outward, and
• a top surface of the first portion is a curved surface protruding outward.