Abstract: Novel rapid-acting human insulin analogues are provided having less tendency to self-association into dimers, tetramers, hexamers, or polymers. The novel human insulin analogues are formed by substituting one or more of the amino acid residues of human insulin with naturally occuring amino acid residues. The amino acid residue substitutions are preferably more hydrophilic than the natural amino acid residue at the respective position in the molecule. Furthermore, the insulin analogues have the same charge or a greater negative charge at neutral pH than that of human insulin. Preferred amino acid substitutions are Asp, Glu, Ser, Thr, His, and Ile, and more preferred substitutions are Asp and Glu. The novel insulin analogues can be used for the preparation of rapid-acting insulin solutions.