Abstract: The present study investigates whether the Matthew Effect exists in L2 vocabulary acquisition from humor-story reading by Chinese EFL learners, i.e., whether learners with a larger existing vocabulary size reap more benefits than learners with a smaller vocabulary size in the long-term vocabulary acquisition.Forty postgraduate students from a key university took part in the experiment.They first read 36 humor and 36 matching non-humor stories and then took an immediate posttest and a delayed posttest.The results indicated that the Matthew Effect existed in reading both the humor and non-humor stories, namely, the rich get richer.Learners with a larger existing vocabulary size and a better story comprehension ability reaped greater long-term vocabulary learning benefits.However, the Matthew Effect varied significantly across the two different story types.In humor-story reading, a threshold effect existed in that learners need to reach a threshold level of story comprehension ability before they can benefit from their existing vocabulary knowledge.In contrast, no such a threshold effect existed in non-humor story reading.