Transcription activator-like effectors (TALEs) are effector proteins secreted by certain plant pathogenic bacteria when infecting their hosts. Upon translocation, TALEs bind via a well-deciphered recognition code to specific sequences in the promoter region of targeted host genes, thereby activating expression of those targeted genes. Gene activation induced by artificially designed TALEs (dTALEs) has been studied in multiple organisms, but is yet to be demonstrated in green algae, such as Chlamydomonas reinhardtii, a well-known model organism for fundamental biological studies, as well as for biofuel production. Our work demonstrates robust gene-specific activation induced by artificially designed TALEs in the green alga Chlamydomonas. The frequency and efficiency of the induced expression demonstrate dTALEs as powerful tools for targeted gene activation in Chlamydomonas. The pattern of activation shown here provides insights into the mechanism of TALE induced expression, and also confirms the activity of the activation domain of naturally occurring TALEs in another organism. Our success with dTALE-induced activation in Chlamydomonas may open a new avenue to fast, high throughput gene manipulation in other related organisms, such as green algae and crop plants.