The construction of novel heterojunction engineering is more favorable for boosting the photocatalytic performance of composite catalysts for emerging contaminants removal. Herein, a spherical-like Mo2C/ZnIn2S4 heterojunction was fabricated via a facile hydrothermal route and then applied as efficient photocatalyst for degrading tetracycline. Benefiting from benign hetero-interface contact and large specific surface area, the prepared catalyst exhibited superior adsorption and photocatalytic activity for contaminants degradation under visible irradiation. Combining with radicals quenching tests and electron spin resonance characterization, the radicals and photo-generated holes were found to be mainly responsible for tetracycline degradation. Moreover, the results of the main degradation intermediates suggested that hydroxylation, dehydration, demethylation, deamination and hydrogenation reduction play major role in degradation processes. The predicted toxicity of degradation intermediates presented that 8 products may cause eco-toxicity. This work provides a facile route for designing spherical-like heterostructured catalysts and sheds lights on sewage remediation by a synergistic adsorption/photocatalysis strategy.