This study examined the effects of spaced practice on second language (L2) vocabulary learning under different learning conditions. One hundred fifty Korean learners of L2 English were divided into five groups: one control (no treatment) and four experimental groups based on learning condition (fill-in-the-blanks vs. flashcards) and spacing type (massed [no spacing interval] vs. spaced [1-day interval]). The participants studied 48 low-frequency English words. Results showed that the effects of spaced practice were greater for fill-in-the-blanks than flashcards on an immediate posttest and that spaced practice was more effective than massed practice for both activities on a 2-week delayed posttest with no overall significant difference between the learning gains from the two activities. Feedback timing (immediate, delayed) did not affect vocabulary learning in either activity.