The invention discloses a manufacturing method of a lamp-cover-supporting LED tubular lamp with a self-clamping heat transmission substrate, and belongs to the technical field of supporting or hanging or connecting of lighting devices. The manufacturing method of the LED tubular lamp includes the steps that S1, the heat transmission substrate is inserted into strip-shaped clamping grooves from side ports of the strip-shaped clamping grooves; S2, after the heat transmission substrate is installed in the strip-shaped clamping grooves, a lamp cover covers a radiator; S3, the lamp cover exerts two acting forces on two T-shaped hooks, and the heat transmission substrate is installed in the strip-shaped clamping grooves in a clamped mode; S4, the radiator, the heat transmission substrate and the lamp cover form a lamp tube of the LED tubular lamp, and two end covers are installed at the two ends of the lamp tube of the LED tubular lamp. According to the lamp-cover-supporting LED tubular lamp with the self-clamping heat transmission substrate, the heat transmission substrate can be arranged in the strip-shaped clamping grooves in the clamped mode because the strip-shaped clamping grooves are formed in an installing part of the heat transmission substrate, heat dissipation efficiency can be improved, and the heat transmission substrate is prevented from thermal deformation.