A tank fixing apparatus comprising: a first band (10; 10b) including a first fixed portion (12; BR) that is fixed to a support member (F; Fa; Fb, B; Fc, B) that supports a tank, a first pressing portion (11; 11b) that extends from the first fixed portion and presses an outer periphery of the tank toward the support member, and a first distal end portion (13; 13b) that extends from the first pressing portion and is not fixed to the support member; an urging portion (30; 30b) that gives a pressing force for the tank to the first band; a first fixing portion (20; W1) that fixes the first fixed portion of the first band to the support member; characterized by further comprising: a second band (50; 50b) including a second fixed portion (52; W2) that is fixed to the support member or the first band, a second pressing portion (51; 51b) that extends from the second fixed portion and presses the tank, and a second distal end portion (53; 53b) that extends from the second pressing portion and is not fixed to the support member; and a second fixing portion (31; W2) that fixes the second fixed portion to the support member or the first band, wherein the second pressing portion of the second band extends between one portion of the first pressing portion and the tank, and presses the tank by an elastic force of the second pressing portion itself, and a direction of the first band extending from the first fixed portion to the first distal end portion is opposite to a direction of the second band extending from the second fixed portion to the second distal end portion. a first band (10; 10b) including a first fixed portion (12; BR) that is fixed to a support member (F; Fa; Fb, B; Fc, B) that supports a tank, a first pressing portion (11; 11b) that extends from the first fixed portion and presses an outer periphery of the tank toward the support member, and a first distal end portion (13; 13b) that extends from the first pressing portion and is not fixed to the support member; an urging portion (30; 30b) that gives a pressing force for the tank to the first band; a first fixing portion (20; W1) that fixes the first fixed portion of the first band to the support member; characterized by further comprising: a second band (50; 50b) including a second fixed portion (52; W2) that is fixed to the support member or the first band, a second pressing portion (51; 51b) that extends from the second fixed portion and presses the tank, and a second distal end portion (53; 53b) that extends from the second pressing portion and is not fixed to the support member; and a second fixing portion (31; W2) that fixes the second fixed portion to the support member or the first band, wherein the second pressing portion of the second band extends between one portion of the first pressing portion and the tank, and presses the tank by an elastic force of the second pressing portion itself, and a direction of the first band extending from the first fixed portion to the first distal end portion is opposite to a direction of the second band extending from the second fixed portion to the second distal end portion. a second band (50; 50b) including a second fixed portion (52; W2) that is fixed to the support member or the first band, a second pressing portion (51; 51b) that extends from the second fixed portion and presses the tank, and a second distal end portion (53; 53b) that extends from the second pressing portion and is not fixed to the support member; and a second fixing portion (31; W2) that fixes the second fixed portion to the support member or the first band, wherein the second pressing portion of the second band extends between one portion of the first pressing portion and the tank, and presses the tank by an elastic force of the second pressing portion itself, and a direction of the first band extending from the first fixed portion to the first distal end portion is opposite to a direction of the second band extending from the second fixed portion to the second distal end portion.