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Cover data of 29 perennial species and 25 environmental variables, in 57 sites, were used to assess vegetation-environment relationships of 16 islands in the coast of Sinaloa, Mexico. The sites were classified through cluster analysis and ordered using detrended correspondence analysis (DCA), then ecological gradients were analyzed with canonical correspondence analysis (CCA). Correlations, species-environment, were significant (P < 0.05) to ten environmental variables. The first axis was related to nitrate (0.776) and pH (-0.584), while the second axis correlated with rocky cover (-0.901), soil depth (0.757), percentage of silt (-0.696), slope (-0.685), and percentage of sand (0.663). These variables were those that best explained the structure of the Sinaloa island vegetation. The effect of such factors is noticeable between island groups: those with addition of seabird guano, islands with rocks of volcanic origin, and those of sandbar.