Golf ball 2 has a core 4, a cover 6 and numerous dimples 8. The cover 6 has a thickness of less than 3.0 mm and a hardness H4 of equal to or greater than 90. A difference (H2-H1) of a surface hardness H2 of the core 4 and a central hardness H1 of the core 4 is 10 or greater and 25 or less. A difference (H4-H1) of the hardness H4 of the cover 6 and a surface hardness H1 of the core 4 is equal to or greater than 25. A difference (H4-H2) of the hardness H4 of the cover 6 and a surface hardness H2 of the core 4 is 10 or greater and 20 or less. Provided that mean diameter of all the dimples 8 is Da, a ratio (N1/N) of number N1 of adjacent dimple pairs having a pitch of (Da/4) or less to total number N of the dimples 8 is equal to or greater than 2.70. A ratio (N2/N1) of number N2 of adjacent dimple pairs having a pitch of (Da/20) or less to the number N1 is equal to or greater than 0.50.