4-alkoxy-N-lauryl-1,8-naphthalimides were synthesized using 4-bromo-1,8-naphthalic anhydride and laurylamine as starting materials through the imidization and substitution reaction. The single factor experiments showed that optimum imidization reaction conditions were n(4-bromo-1,8-naphthalic anhydride) : n(laurylamine) =1:1.1, reaction temperature 50℃, reaction time 4 h. Under this conditions, the yield of intermediate product 4-bromo-N-lauryl-1,8-naphthalimide was 79.4%. Structures of the final products 4-alkoxy-N-lauryl-1,8-naphthalimides were characterized by IR and 1HNMR. The test results of UV absorption and fluorescent spectrum showed that the target product of the maximum absorption in absolute alcohol was 357nm and 342nm, and the maximum emission was 485nm and 490 nm, respectively. The fluorescent quantum yields of the dyes in DMF were over 0.6.