The effect of molecular weight and long-chain branching on the crystallization analysis fractionation (CRYSTAF) of ethylene homopolymers was investigated. Several ethylene homopolymers were prepared with different molecular weights and levels of long-chain branching to isolate these effects from the dominant effect of comonomer content on crystallizability measured by CRYSTAF. Molecular weight effects might be significant for samples with number-average molecular weights below 5000, but this effect can be corrected if terminal methyl groups are taken into account. Long-chain branching has only a very small effect on the CRYSTAF profile of the samples investigated in this study.