In this paper, the scaled group consensus problem of high-order multi-agent systems is investigated over directed graphs. In terms of an appropriate Lyapunov function, sufficient conditions are derived to guarantee scaled consensus for high-order continuous-time systems for strongly connected networks. For the case where the agents are subject to exogenous inputs, the scaled consensus is achieved with a guaranteed / performance. Moreover, the scaled-consensus problem for multiagents subject Denial-of-Service (DoS) attack is investigated. The considered attack model allows the adversaries to compromise agents independently. Decay rates for each attack mode are obtained based on a set of linear matrix inequalities. Sufficient conditions in terms of decay rates are derived to guarantee secure scaled consensus. Simulation results are also presented to illustrate the effectiveness of the proposed theoretical results.