This study examines the effect of acquisitions worldwide on R&D intensity of acquiring firms. Acquisitions on one hand could help acquirers with accessing innovation capabilities of target firms. On the other hand, R&D intensity of acquirers decreases after acquisitions because of integration problems between the acquirer and the target. The results do not show strong evidence that R&D intensity significantly changes after acquisitions in general. Industry relatedness and the listing status of targets do not seem to matter in regards to acquirers’ future R&D intensity, either. However, R&D intensity appears to be influenced by whether or not acquirers operate in industries with high R&D intensity. Moreover, R&D intensity of acquirers increases after cross-border acquisitions when cultural distance is high and the income level is similar between the acquirer and the target countries. An increase in R&D intensity is more pronounced when acquirers are not American firms.