This work presents a comprehensive review on the use of bio-inhibitors for stabilizing gas/oil shales during drilling and hydraulic fracturing. The swelling and dispersion inhibiting potentials and mechanisms of 23 bio-inhibitors were analytically reviewed and compared with existing conventional inhibitors. Relevant data on the influence of bio-inhibitors to shale swelling, YP, contact angle, and zeta potential is provided. Also, the toxicity, biodegradability and production viability of bio-inhibitors are discussed. The review indicated that bio-inhibitors are potential candidates for clay swelling inhibition considering their low-cost, performance and environmental friendliness. The work provides guidelines and recommendations in selecting efficient shale destabilization inhibitors. © 2020 Elsevier B.V.