This paper considers an anisotropic swarm model with an attraction/repulsion function under external profiles. We study its aggregation properties and show that the swarm members will aggregate and eventually form a cohesive cluster of finite size around their weighted center in a finite time. In the model, the motion of each agent is a combination of the interindividual interactions and the interaction of the agent with external environment. Numerical simulations demonstrate that all agents will eventually enter and remain in a bounded region around the weighted center. The swarm may exhibit complex oscillatory or spiral motion due to the asymmetry of the coupling structure and the effect of the external profile. The model in this paper is more general than isotropic swarms and our results provide further insight into the effect of the interaction pattern and the external profile on individual motion in a swarm system.