Efficient color converters are essential for achieving high −3-dB bandwidths and net data rates in optical wireless communications (OWCs). Here, we emphasize the significance of lanthanide-based metal–organic frameworks (MOFs) combined with an effective energy transfer strategy for developing high-performance color converters in OWC systems. In this approach, we successfully reduced the photoluminescence (PL) lifetime from 1.3 ms of the MOF to 4.6 ns of the MOF–chromophore composite, achieved through an efficient energy transfer process in the cavity and surface of the MOFs. This significant reduction in PL lifetime led to a dramatic increase in the −3-dB bandwidth, rising from less than 0.1 to 65.7 MHz. Most importantly, a net data rate of 1.076 GB/s was achieved, marking the first successful demonstration of lanthanide-based MOFs as color converters that facilitate data transmission rates exceeding 1 GB/s. Notably, both the −3-dB bandwidth and net data rate surpass those of most reported organic and inorganic materials, underscoring the exceptional potential of lanthanide-based MOFs when combined with an efficient energy transfer strategy. We believe this combination paves the way for further innovations in high-speed OWC technologies.