Provided is a pneumatic tire including a sidewall that has a good balance of excellent handling stability, rolling resistance, and durability and further has excellent flex crack growth resistance. The sidewall is formed from a modified cellulose fiber-containing rubber composition that is allowed to simultaneously achieve excellent rigidity, excellent tensile properties, and low energy loss by improving the dispersibility of the cellulose fiber in rubber. The present invention relates to a pneumatic tire including a sidewall formed from a modified cellulose fiber-containing rubber composition, the modified cellulose fiber-containing rubber composition containing a modified cellulose fiber (A) obtained by adding a C15 or higher cyclic polybasic acid anhydride (a) containing a hydrophobic group to a cellulose fiber through esterification, a dispersing polymer (B) having a softening point of 135° C. or lower, and a rubber component (C).