A variable composite support structure for supporting an electronic product, comprising: a base, having a flexible block and is anti-slip, and an inner side of a longer side of the base is provided with a first guide channel, such that a location close to an end portion of the first guide channel is provided with a second guide channel that is perpendicular to the first guide channel; a support block, which is flexible and anti-slip, an end portion of the support block is provided with a first guide rail, and an adjacent end of the support block is formed with a first connecting channel, such that a bottom of a corresponding end portion of the first connecting channel is provided with a side rail; a connecting block, which is flexible and anti-slip, an end portion of the connecting block is provided with a second guide rail, and an adjacent end portion of the connecting block is formed with a second connecting channel, such that a corresponding end portion of the second connecting channel is extended with a first connecting rail; and an extension block, which is flexible and anti-slip and two adjacent ends of the extension block are provided with a second connecting rail,, respectively; wherein the base, the support block, the connecting block and the extension block, are combined and configured to slide freely the rails,,,,, of the support block, the connecting block and the extension block in the guide channels, of the base, such that a gap between the base and the support block, the connecting block and the extension block is adjustable, and an inclined angle for clamping an object is controllable; are combined, characterised in that the base is a substantially L-shaped block. a base, having a flexible block and is anti-slip, and an inner side of a longer side of the base is provided with a first guide channel, such that a location close to an end portion of the first guide channel is provided with a second guide channel that is perpendicular to the first guide channel; a support block, which is flexible and anti-slip, an end portion of the support block is provided with a first guide rail, and an adjacent end of the support block is formed with a first connecting channel, such that a bottom of a corresponding end portion of the first connecting channel is provided with a side rail; a connecting block, which is flexible and anti-slip, an end portion of the connecting block is provided with a second guide rail, and an adjacent end portion of the connecting block is formed with a second connecting channel, such that a corresponding end portion of the second connecting channel is extended with a first connecting rail; and an extension block, which is flexible and anti-slip and two adjacent ends of the extension block are provided with a second connecting rail,, respectively; wherein the base, the support block, the connecting block and the extension block, are combined and configured to slide freely the rails,,,,, of the support block, the connecting block and the extension block in the guide channels, of the base, such that a gap between the base and the support block, the connecting block and the extension block is adjustable, and an inclined angle for clamping an object is controllable; are combined, characterised in that the base is a substantially L-shaped block.