A　step-economic　strategy　for　3-aminoindoles　synthesis　with　ammonia　or　primary　amines　as　＂N＂　source　under　transition-metal-free　conditions　was　achieved.　A　series　of　3-aminoindoles　was　obtained　with　abundant　＂N＂　source　featuring　high　efficiency,　mild　conditions,　environmental　friendliness　and　scalability.　Efficient　syntheses　of　the　intermediates　of　COX-2　inhibitor　and　tubulin　polymerization　inhibitor　were　successfully　accomplished　with　this　newly　developed　strategy.